Update stock/hsx.vn.md

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2026-07-08 14:20:19 +07:00 · 2026-07-08 14:20:00 +07:00 · 2026-07-08 13:53:49 +07:00 · 2026-07-08 13:53:01 +07:00 · 2026-07-05 14:09:57 +03:00 · 2026-07-04 21:40:29 +03:00
272 changed files with 13348 additions and 4828 deletions
@@ -1,28 +1,29 @@
-FROM node:16-bullseye
+FROM node:16-bookworm

 WORKDIR /root

-ADD ./docker/vitastor.gpg /etc/apt/trusted.gpg.d
+ADD ./docker/etc/apt/trusted.gpg.d /etc/apt/trusted.gpg.d

-RUN echo 'deb http://deb.debian.org/debian bullseye-backports main' >> /etc/apt/sources.list; \
-    echo 'deb http://vitastor.io/debian bullseye main' >> /etc/apt/sources.list; \
+RUN echo 'deb http://deb.debian.org/debian bookworm-backports main' >> /etc/apt/sources.list; \
+    echo 'deb http://vitastor.io/debian bookworm main' >> /etc/apt/sources.list; \
    echo >> /etc/apt/preferences; \
    echo 'Package: *' >> /etc/apt/preferences; \
-    echo 'Pin: release a=bullseye-backports' >> /etc/apt/preferences; \
+    echo 'Pin: release n=bookworm-backports' >> /etc/apt/preferences; \
    echo 'Pin-Priority: 500' >> /etc/apt/preferences; \
    echo >> /etc/apt/preferences; \
    echo 'Package: *' >> /etc/apt/preferences; \
    echo 'Pin: origin "vitastor.io"' >> /etc/apt/preferences; \
    echo 'Pin-Priority: 1000' >> /etc/apt/preferences; \
+    perl -i -pe 's/Types: deb$/Types: deb deb-src/' /etc/apt/sources.list.d/debian.sources; \
    grep '^deb ' /etc/apt/sources.list | perl -pe 's/^deb/deb-src/' >> /etc/apt/sources.list; \
    echo 'APT::Install-Recommends false;' >> /etc/apt/apt.conf; \
    echo 'APT::Install-Suggests false;' >> /etc/apt/apt.conf

 RUN apt-get update
-RUN apt-get -y install etcd qemu-system-x86 qemu-block-extra qemu-utils fio libasan5 \
+RUN apt-get -y install etcd qemu-system-x86 qemu-block-extra qemu-utils fio libasan8 \
    libgoogle-perftools-dev devscripts libjerasure-dev cmake libibverbs-dev libisal-dev
 RUN apt-get -y build-dep fio qemu=`dpkg -s qemu-system-x86|grep ^Version:|awk '{print $2}'`
-RUN apt-get update && apt-get -y install jq lp-solve sudo nfs-common fdisk parted
+RUN apt-get update && apt-get -y install jq lp-solve sudo nfs-common fdisk parted libc-ares-dev udev
 RUN apt-get --download-only source fio qemu=`dpkg -s qemu-system-x86|grep ^Version:|awk '{print $2}'`

 RUN set -ex; \
@@ -63,7 +63,7 @@ jobs:
    container: ${{env.TEST_IMAGE}}:${{github.sha}}
    steps:
    # leak sanitizer sometimes crashes
-    - run: cd /root/vitastor/build && ASAN_OPTIONS=detect_leaks=0 make -j16 test
+    - run: cd /root/vitastor/build && ASAN_OPTIONS=detect_leaks=0 make -j16 build_tests test

  npm_lint:
    runs-on: ubuntu-latest
@@ -306,6 +306,78 @@ jobs:
          echo ""
        done

+  test_dump_load:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_dump_load.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_dump_load_32k:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: TEST_NAME=32k OSD_ARGS="--data_csum_type crc32c --csum_block_size 32k" OFFSET_ARGS="$OSD_ARGS" /root/vitastor/tests/test_dump_load.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_old_dump_load:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: OLD=1 /root/vitastor/tests/test_dump_load.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_dump_load_old_32k:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: TEST_NAME=old_32k OLD=1 OSD_ARGS="--data_csum_type crc32c --csum_block_size 32k" OFFSET_ARGS="$OSD_ARGS" /root/vitastor/tests/test_dump_load.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
  test_old_interrupted_rebalance:
    runs-on: ubuntu-latest
    needs: build
@@ -414,6 +486,24 @@ jobs:
          echo ""
        done

+  test_level_placement:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_level_placement.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
  test_snapshot:
    runs-on: ubuntu-latest
    needs: build
@@ -1188,6 +1278,78 @@ jobs:
          echo ""
        done

+  test_checksum:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_checksum.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_old_checksum:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: OLD=1 /root/vitastor/tests/test_checksum.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_corrupt_all:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_corrupt_all.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_old_corrupt_all:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: OLD=1 /root/vitastor/tests/test_corrupt_all.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
  test_reweight_half:
    runs-on: ubuntu-latest
    needs: build
@@ -1368,6 +1530,24 @@ jobs:
          echo ""
        done

+  test_resize_last:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_resize_last.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
  test_resize_auto:
    runs-on: ubuntu-latest
    needs: build
@@ -1404,6 +1584,24 @@ jobs:
          echo ""
        done

+  test_old_resize_last:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: OLD=1 /root/vitastor/tests/test_resize_last.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
  test_old_resize_auto:
    runs-on: ubuntu-latest
    needs: build
@@ -1800,6 +1998,24 @@ jobs:
          echo ""
        done

+  test_old_partwr_csum:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: OLD=1 /root/vitastor/tests/test_partwr_csum.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
  test_heal_old_csum_32k_dmj:
    runs-on: ubuntu-latest
    needs: build
@@ -1926,3 +2142,21 @@ jobs:
          echo ""
        done

+  test_nfs_unaligned_append:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_nfs_unaligned_append.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
@@ -1,20 +1,20 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 2.8...3.30)

 project(vitastor)

-set(VITASTOR_VERSION "3.0.0")
+set(VITASTOR_VERSION "3.0.15")

 include(CTest)

 add_custom_target(build_tests)
-add_custom_target(test
-	COMMAND
-	echo leak:tcmalloc > ${CMAKE_CURRENT_BINARY_DIR}/lsan-suppress.txt &&
-	env LSAN_OPTIONS=suppressions=${CMAKE_CURRENT_BINARY_DIR}/lsan-suppress.txt ${CMAKE_CTEST_COMMAND}
+set_property(TEST PROPERTY ENVIRONMENT LSAN_OPTIONS=suppressions=${CMAKE_CURRENT_BINARY_DIR}/lsan-suppress.txt)
+add_test(gen_lsan_suppress
+    ${CMAKE_COMMAND} -E echo leak:tcmalloc > "${CMAKE_CURRENT_BINARY_DIR}/lsan-suppress.txt"
 )
+set_tests_properties(gen_lsan_suppress PROPERTIES FIXTURES_SETUP f_lsan_suppress)
+set_property(TEST PROPERTY FIXTURES_REQUIRED f_lsan_suppress)
 # make -j16 -C ../../build test_heap && ../../build/src/test/test_heap
 # make -j16 -C ../../build test_heap && rm -f $(find ../../build -name '*.gcda') && ctest -V -T test -T coverage -R heap --test-dir ../../build && (cd ../../build; gcovr -f ../src --html --html-nested -o coverage/index.html; cd ../src/test)
 # make -j16 -C ../../build test_blockstore && rm -f $(find ../../build -name '*.gcda') && ctest -V -T test -T coverage -R blockstore --test-dir ../../build && (cd ../../build; gcovr -f ../src --html --html-nested -o coverage/index.html; cd ../src/test)
 # kcov --include-path=../../../src ../../kcov ./test_blockstore
-add_dependencies(test build_tests)
 add_subdirectory(src)
@@ -1,112 +1,183 @@
-# Vitastor
+# tromcho.net

-[Читать на русском](README-ru.md)
+Repository này chứa toàn bộ source code của website **tromcho.net**.

-## The Idea
+## Giới thiệu

-Make Clustered Block Storage Fast Again.
+`tromcho.net` là mã nguồn website được tổ chức để phục vụ phát triển, triển khai và vận hành theo quy trình chuẩn trên GitHub.
+README này đóng vai trò tài liệu khởi đầu cho lập trình viên, DevOps engineer và cộng tác viên khi tiếp cận repository.

-Vitastor is a distributed block, file and object SDS, direct replacement of Ceph RBD, CephFS and RGW,
-and also internal SDS's of public clouds. However, in contrast to them, Vitastor is fast
-and simple at the same time. The only thing is it's slightly young :-).
+## Mục tiêu repository

-Vitastor is architecturally similar to Ceph which means strong consistency,
-primary-replication, symmetric clustering and automatic data distribution over any
-number of drives of any size with configurable redundancy (replication or erasure codes/XOR).
+- Quản lý tập trung toàn bộ source code của website.
+- Chuẩn hóa quy trình phát triển, review và triển khai.
+- Tạo nền tảng rõ ràng cho việc CI/CD, kiểm thử và vận hành production.
+- Hỗ trợ onboarding nhanh cho thành viên mới.

-Vitastor targets primarily SSD and SSD+HDD clusters with at least 10 Gbit/s network,
-supports TCP and RDMA and may achieve 4 KB read and write latency as low as ~0.1 ms
-with proper hardware which is ~10 times faster than other popular SDS's like Ceph
-or internal systems of public clouds.
+## Cấu trúc thư mục đề xuất

-Vitastor supports QEMU, UBLK, NBD, NFS protocols, OpenStack, OpenNebula, Proxmox, Kubernetes drivers.
-More drivers may be created easily.
+```text
+.
+├── app/                # Source code ứng dụng chính
+├── public/             # Static files, images, favicon, robots.txt
+├── config/             # Cấu hình môi trường, app, service integration
+├── database/           # Migration, seed, schema
+├── tests/              # Unit test, integration test, e2e test
+├── scripts/            # Script hỗ trợ build, deploy, backup, maintenance
+├── docs/               # Tài liệu kỹ thuật, kiến trúc, quy trình
+├── .github/            # GitHub Actions, issue template, PR template
+├── Dockerfile          # Build image ứng dụng
+├── docker-compose.yml  # Chạy local/dev bằng container
+├── .env.example        # Biến môi trường mẫu
+└── README.md
+```

-Read more details in the documentation. You can start from here: [Quick Start](docs/intro/quickstart.en.md).
+> Cấu trúc thực tế có thể thay đổi theo framework đang sử dụng.

-## Talks and presentations
+## Yêu cầu môi trường

- KuberConf'2025: [video](https://vitastor.io/presentation/kuberconf.webm)
- Highload'2025: [video](https://vitastor.io/presentation/hl2025/hl2025.webm),
-  [youtube](https://www.youtube.com/watch?v=0R8MLjFtz7g), presentation
-  ([in Russian](https://vitastor.io/presentation/hl2025/), [in English](https://vitastor.io/presentation/hl2025/en.html))
- Highload'2022: presentation ([in Russian](https://vitastor.io/presentation/highload/highload.html)),
-  [video](https://vitastor.io/presentation/highload/talk.webm)
- DevOpsConf'2021: presentation ([in Russian](https://vitastor.io/presentation/devopsconf/devopsconf.html),
-  [in English](https://vitastor.io/presentation/devopsconf/devopsconf_en.html)),
-  [video](https://vitastor.io/presentation/devopsconf/talk.webm)
+Tùy theo stack công nghệ của website, môi trường phát triển nên có:

-## Documentation
+- Git
+- Docker và Docker Compose
+- Node.js / PHP / Python / runtime phù hợp với dự án
+- Make (khuyến nghị)
+- Truy cập vào file cấu hình môi trường `.env`

- Introduction
-  - [Quick Start](docs/intro/quickstart.en.md)
-  - [Features](docs/intro/features.en.md)
-  - [Architecture](docs/intro/architecture.en.md)
-  - [Author and license](docs/intro/author.en.md)
- Installation
-  - [Packages](docs/installation/packages.en.md)
-  - [Docker](docs/installation/docker.en.md)
-  - [Proxmox](docs/installation/proxmox.en.md)
-  - [OpenNebula](docs/installation/opennebula.en.md)
-  - [OpenStack](docs/installation/openstack.en.md)
-  - [Kubernetes CSI](docs/installation/kubernetes.en.md)
-  - [S3](docs/installation/s3.en.md)
-  - [Building from Source](docs/installation/source.en.md)
- Configuration
-  - [Overview](docs/config.en.md)
-  - Parameter Reference
-    - [Common](docs/config/common.en.md)
-    - [Network](docs/config/network.en.md)
-    - [Client](docs/config/client.en.md)
-    - [Global Disk Layout](docs/config/layout-cluster.en.md)
-    - [OSD Disk Layout](docs/config/layout-osd.en.md)
-    - [OSD Runtime Parameters](docs/config/osd.en.md)
-    - [Monitor](docs/config/monitor.en.md)
-  - [Pool configuration](docs/config/pool.en.md)
-  - [Image metadata in etcd](docs/config/inode.en.md)
- Usage
-  - [vitastor-cli](docs/usage/cli.en.md) (command-line interface)
-  - [vitastor-disk](docs/usage/disk.en.md) (disk management tool)
-  - [fio](docs/usage/fio.en.md) for benchmarks
-  - [UBLK](docs/usage/ublk.en.md) for kernel mounts
-  - [NBD](docs/usage/nbd.en.md) - old interface for kernel mounts
-  - [QEMU, qemu-img and VDUSE](docs/usage/qemu.en.md)
-  - [NFS](docs/usage/nfs.en.md) clustered file system and pseudo-FS proxy
-  - [Administration](docs/usage/admin.en.md)
- Performance
-  - [Understanding storage performance](docs/performance/understanding.en.md)
-  - [Theoretical performance](docs/performance/theoretical.en.md)
-  - [Example comparison with Ceph](docs/performance/comparison1.en.md)
-  - [Newer benchmark of Vitastor 1.3.1](docs/performance/bench2.en.md)
+## Bắt đầu nhanh

-## Author and License
+### 1. Clone repository

-Copyright (c) Vitaliy Filippov (vitalif [at] yourcmc.ru), 2019+
+```bash
+git clone https://github.com/<your-org>/tromcho.net.git
+cd tromcho.net
+```

-Join Vitastor Telegram Chat: https://t.me/vitastor
+### 2. Tạo file môi trường

-All server-side code (OSD, Monitor and so on) is licensed under the terms of
-Vitastor Network Public License 1.1 (VNPL 1.1), a copyleft license based on
-GNU GPLv3.0 with the additional "Network Interaction" clause which requires
-opensourcing all programs directly or indirectly interacting with Vitastor
-through a computer network and expressly designed to be used in conjunction
-with it ("Proxy Programs"). Proxy Programs may be made public not only under
-the terms of the same license, but also under the terms of any GPL-Compatible
-Free Software License, as listed by the Free Software Foundation.
-This is a stricter copyleft license than the Affero GPL.
+```bash
+cp .env.example .env
+```

-Please note that VNPL doesn't require you to open the code of proprietary
-software running inside a VM if it's not specially designed to be used with
-Vitastor.
+Sau đó cập nhật các biến cấu hình cần thiết trong file `.env`.

-Basically, you can't use the software in a proprietary environment to provide
-its functionality to users without opensourcing all intermediary components
-standing between the user and Vitastor or purchasing a commercial license
-from the author 😀.
+### 3. Chạy môi trường local

-Client libraries (cluster_client and so on) are dual-licensed under the same
-VNPL 1.1 and also GNU GPL 2.0 or later to allow for compatibility with GPLed
-software like QEMU and fio.
+Nếu dự án dùng Docker:

-You can find the full text of VNPL-1.1 in the file [VNPL-1.1.txt](VNPL-1.1.txt).
-GPL 2.0 is also included in this repository as [GPL-2.0.txt](GPL-2.0.txt).
+```bash
+docker compose up -d --build
+```
+
+Nếu dự án chạy trực tiếp theo framework, sử dụng lệnh tương ứng của stack hiện tại.
+
+## Quy trình phát triển
+
+- Tạo branch mới từ `main` hoặc `develop`.
+- Đặt tên branch rõ ràng, ví dụ: `feature/homepage-banner`, `fix/login-timeout`.
+- Commit ngắn gọn, đúng ngữ cảnh thay đổi.
+- Tạo Pull Request để review trước khi merge.
+- Không commit file bí mật như `.env`, private key hoặc credential.
+
+## Quy ước commit
+
+Khuyến nghị dùng convention sau:
+
+```text
+feat: thêm chức năng mới
+fix: sửa lỗi
+refactor: tái cấu trúc mã nguồn
+chore: cập nhật tác vụ phụ trợ
+ci: thay đổi pipeline CI/CD
+docs: cập nhật tài liệu
+test: bổ sung hoặc cập nhật kiểm thử
+```
+
+## CI/CD
+
+Repository nên tích hợp các bước tự động sau:
+
+- Lint source code
+- Chạy unit test / integration test
+- Build artifact hoặc Docker image
+- Scan bảo mật dependency/container
+- Deploy tới staging hoặc production theo rule xác định
+
+Ví dụ vị trí cấu hình pipeline:
+
+```text
+.github/workflows/
+```
+
+## Biến môi trường
+
+Không commit file `.env` thật lên GitHub.
+Nên cung cấp `.env.example` với:
+
+- Danh sách biến bắt buộc
+- Giá trị mẫu an toàn
+- Ghi chú ngắn cho từng biến quan trọng
+
+Ví dụ:
+
+```env
+APP_ENV=local
+APP_DEBUG=true
+APP_URL=http://localhost
+DB_HOST=127.0.0.1
+DB_PORT=3306
+DB_NAME=tromcho
+DB_USER=user
+DB_PASSWORD=change_me
+```
+
+## Triển khai
+
+Khuyến nghị tách rõ các môi trường:
+
+- local
+- development
+- staging
+- production
+
+Các thành phần nên được chuẩn hóa khi triển khai:
+
+- Biến môi trường
+- Reverse proxy / web server
+- TLS certificate
+- Database migration
+- Backup strategy
+- Log rotation và monitoring
+
+## Bảo mật
+
+- Không đưa secrets vào source code.
+- Bật branch protection cho nhánh quan trọng.
+- Review dependency định kỳ.
+- Áp dụng nguyên tắc least privilege cho tài khoản deploy.
+- Theo dõi log, audit và cảnh báo bất thường.
+
+## Đóng góp
+
+Khi đóng góp vào repository:
+
+1. Fork hoặc tạo branch làm việc.
+2. Cập nhật mã nguồn theo phạm vi thay đổi.
+3. Kiểm tra local trước khi tạo Pull Request.
+4. Viết mô tả PR rõ ràng: mục tiêu, phạm vi ảnh hưởng, cách kiểm thử.
+
+## Tài liệu nên bổ sung
+
+Repository này nên có thêm các tài liệu sau trong thư mục `docs/`:
+
+- Kiến trúc hệ thống
+- Sơ đồ database
+- Luồng deploy
+- Quy trình backup/restore
+- Hướng dẫn xử lý sự cố
+- Checklist release
+
+## License
+
+Copyright 2026 Trộm Chó chấm Nét
+---
@@ -1,5 +1,5 @@
 # Compile stage
-FROM golang:bookworm AS build
+FROM golang:trixie AS build

 ADD go.sum go.mod /app/
 RUN cd /app; CGO_ENABLED=1 GOOS=linux GOARCH=amd64 go mod download -x
@@ -9,7 +9,7 @@ RUN perl -i -e '$/ = undef; while(<>) { s/\n\s*(\{\s*\n)/$1\n/g; s/\}(\s*\n\s*)e
    CGO_ENABLED=1 GOOS=linux GOARCH=amd64 go build -o vitastor-csi

 # Final stage
-FROM debian:bookworm
+FROM debian:trixie

 LABEL maintainers="Vitaliy Filippov <vitalif@yourcmc.ru>"
 LABEL description="Vitastor CSI Driver"
@@ -25,20 +25,20 @@ RUN apt-get update && \
        # NFS mount dependencies
        nfs-common netbase \
        # dependencies of qemu-storage-daemon
-        libnuma1 liburing2 libglib2.0-0 libfuse3-3 libaio1 libzstd1 libnettle8 \
-        libgmp10 libhogweed6 libp11-kit0 libidn2-0 libunistring2 libtasn1-6 libpcre2-8-0 libffi8 && \
+        libaio1t64 libc6 libfuse3-4 libglib2.0-0t64 libgmp10 libgnutls30t64 \
+        libhogweed6t64 libnettle8t64 libnuma1 libselinux1 liburing2 libzstd1 zlib1g && \
    apt-get clean && \
    (echo options nbd nbds_max=128 > /etc/modprobe.d/nbd.conf)

 COPY --from=build /app/vitastor-csi /bin/

-RUN (echo deb http://vitastor.io/debian bookworm main > /etc/apt/sources.list.d/vitastor.list) && \
+RUN (echo deb http://vitastor.io/debian trixie main > /etc/apt/sources.list.d/vitastor.list) && \
    ((echo 'Package: *'; echo 'Pin: origin "vitastor.io"'; echo 'Pin-Priority: 1000') > /etc/apt/preferences.d/vitastor.pref) && \
    wget -q -O /etc/apt/trusted.gpg.d/vitastor.gpg https://vitastor.io/debian/pubkey.gpg && \
    apt-get update && \
    apt-get install -y vitastor-client ibverbs-providers && \
-    wget https://vitastor.io/archive/qemu/qemu-bookworm-9.2.2%2Bds-1%2Bvitastor4/qemu-utils_9.2.2%2Bds-1%2Bvitastor4_amd64.deb && \
-    wget https://vitastor.io/archive/qemu/qemu-bookworm-9.2.2%2Bds-1%2Bvitastor4/qemu-block-extra_9.2.2%2Bds-1%2Bvitastor4_amd64.deb && \
+    wget https://vitastor.io/archive/qemu/qemu-trixie-10.0.2%2Bds-2%2Bvitastor1/qemu-utils_10.0.2%2Bds-2%2Bvitastor1_amd64.deb && \
+    wget https://vitastor.io/archive/qemu/qemu-trixie-10.0.2%2Bds-2%2Bvitastor1/qemu-block-extra_10.0.2%2Bds-2%2Bvitastor1_amd64.deb && \
    dpkg -x qemu-utils*.deb tmp1 && \
    dpkg -x qemu-block-extra*.deb tmp1 && \
    cp -a tmp1/usr/bin/qemu-storage-daemon /usr/bin/ && \
@@ -1,5 +1,5 @@
 # Compile stage
-FROM golang:bookworm AS build
+FROM golang:trixie AS build

 ADD go.sum go.mod /app/
 RUN cd /app; CGO_ENABLED=1 GOOS=linux GOARCH=amd64 go mod download -x
@@ -9,7 +9,7 @@ RUN perl -i -e '$/ = undef; while(<>) { s/\n\s*(\{\s*\n)/$1\n/g; s/\}(\s*\n\s*)e
    CGO_ENABLED=1 GOOS=linux GOARCH=amd64 go build -o vitastor-csi

 # Final stage
-FROM debian:bookworm
+FROM debian:trixie

 LABEL maintainers="Vitaliy Filippov <vitalif@yourcmc.ru>"
 LABEL description="Vitastor CSI Driver"
@@ -36,8 +36,8 @@ ADD deb /deb

 RUN apt-get update && \
    apt-get -y install /deb/vitastor-client_*.deb && \
-    wget https://vitastor.io/archive/qemu/qemu-bookworm-9.2.2%2Bds-1%2Bvitastor4/qemu-utils_9.2.2%2Bds-1%2Bvitastor4_amd64.deb && \
-    wget https://vitastor.io/archive/qemu/qemu-bookworm-9.2.2%2Bds-1%2Bvitastor4/qemu-block-extra_9.2.2%2Bds-1%2Bvitastor4_amd64.deb && \
+    wget https://vitastor.io/archive/qemu/qemu-trixie-9.2.2%2Bds-1%2Bvitastor4/qemu-utils_9.2.2%2Bds-1%2Bvitastor4_amd64.deb && \
+    wget https://vitastor.io/archive/qemu/qemu-trixie-9.2.2%2Bds-1%2Bvitastor4/qemu-block-extra_9.2.2%2Bds-1%2Bvitastor4_amd64.deb && \
    dpkg -x qemu-utils*.deb tmp1 && \
    dpkg -x qemu-block-extra*.deb tmp1 && \
    cp -a tmp1/usr/bin/qemu-storage-daemon /usr/bin/ && \
@@ -1,4 +1,4 @@
-VITASTOR_VERSION ?= v3.0.0
+VITASTOR_VERSION ?= v3.0.15

 all: build push

@@ -49,7 +49,7 @@ spec:
            capabilities:
              add: ["SYS_ADMIN"]
            allowPrivilegeEscalation: true
-          image: vitalif/vitastor-csi:v3.0.0
+          image: vitalif/vitastor-csi:v3.0.15
          args:
            - "--node=$(NODE_ID)"
            - "--endpoint=$(CSI_ENDPOINT)"
@@ -121,7 +121,7 @@ spec:
            privileged: true
            capabilities:
              add: ["SYS_ADMIN"]
-          image: vitalif/vitastor-csi:v3.0.0
+          image: vitalif/vitastor-csi:v3.0.15
          args:
            - "--node=$(NODE_ID)"
            - "--endpoint=$(CSI_ENDPOINT)"
@@ -5,7 +5,7 @@ package vitastor

 const (
    vitastorCSIDriverName    = "csi.vitastor.io"
-    vitastorCSIDriverVersion = "3.0.0"
+    vitastorCSIDriverVersion = "3.0.15"
 )

 // Config struct fills the parameters of request or user input
@@ -0,0 +1,5 @@
+#!/bin/bash
+# 26.04 Resolute Raccoon
+
+docker build --build-arg DISTRO=ubuntu --build-arg REL=resolute -t vitastor-buildenv:resolute -f vitastor-buildenv.Dockerfile .
+docker run -it --rm -e REL=resolute -v `dirname $0`/../:/root/vitastor vitastor-buildenv:resolute /root/vitastor/debian/vitastor-build.sh
@@ -1,4 +1,4 @@
-vitastor (3.0.0-1) unstable; urgency=medium
+vitastor (3.0.15-1) unstable; urgency=medium

  * Bugfixes

@@ -11,6 +11,7 @@ override_dh_install:
 	cp -v node-binding/package.json node-binding/index.js node-binding/addon.cc node-binding/addon.h node-binding/client.cc node-binding/client.h debian/tmp/usr/lib/x86_64-linux-gnu/nodejs/vitastor
 	cp -v node-binding/build/Release/addon.node debian/tmp/usr/lib/x86_64-linux-gnu/nodejs/vitastor/build/Release
 	dh_install
+	cd debian/vitastor-mon/usr/lib/vitastor/mon && npm install --production

 override_dh_installdeb:
 	cat debian/fio_version >> debian/vitastor-fio.substvars
@@ -37,14 +37,8 @@ rm -rf a b

 echo "dep:fio=$FIO" > debian/fio_version

-cd /root/vitastor/packages/vitastor-$REL/vitastor-$VER
-mkdir mon/node_modules
-cd mon/node_modules
-curl -s https://git.yourcmc.ru/vitalif/antietcd/archive/master.tar.gz | tar -zx
-curl -s https://git.yourcmc.ru/vitalif/tinyraft/archive/master.tar.gz | tar -zx
-
 cd /root/vitastor/packages/vitastor-$REL
-if [[ "$REL" = "trixie" && -e ../vitastor-bookworm/vitastor_$VER.orig.tar.xz ]]; then
+if [[ ( "$REL" = "trixie" || "$REL" = "resolute" ) && -e ../vitastor-bookworm/vitastor_$VER.orig.tar.xz ]]; then
    # Fucking shit, archives differ between bookworm (xz 5.4.1) and trixie (xz 5.8.1)
    cp ../vitastor-bookworm/vitastor_$VER.orig.tar.xz .
 else
@@ -1,6 +1,6 @@
 # Build Docker image with Vitastor packages

-FROM debian:bookworm
+FROM debian:trixie

 ADD etc/apt /etc/apt/
 RUN apt-get update && apt-get -y install vitastor ibverbs-providers udev systemd qemu-system-x86 qemu-system-common qemu-block-extra qemu-utils jq nfs-common && apt-get clean
@@ -1,4 +1,4 @@
-VITASTOR_VERSION ?= v3.0.0
+VITASTOR_VERSION ?= v3.0.15

 all: build push

@@ -1,3 +1,3 @@
 Package: *
-Pin: release n=bookworm-backports
+Pin: release n=trixie-backports
 Pin-Priority: 500
@@ -1,2 +1,2 @@
-deb http://vitastor.io/debian bookworm main
-deb http://http.debian.net/debian/ bookworm-backports main
+deb http://vitastor.io/debian trixie main
+#deb http://http.debian.net/debian/ trixie-backports main
@@ -7,7 +7,7 @@ PartOf=vitastor.target
 [Service]
 Restart=always
 EnvironmentFile=/etc/vitastor/docker.conf
-ExecStart=bash -c 'docker run --rm -i -v /etc/vitastor:/etc/vitastor -v /dev:/dev -v /run:/run \
+ExecStart=bash -c 'docker run --rm -i -v /etc/vitastor:/etc/vitastor -v /dev:/dev -v /run:/run -e SYSTEMD_IN_CHROOT=0 \
    --security-opt seccomp=unconfined --privileged --pid=host --log-driver none --network host --name vitastor vitastor:$VITASTOR_VERSION \
    sleep.sh'
 ExecStartPost=udevadm trigger
@@ -4,7 +4,7 @@
 #

 # Desired Vitastor version
-VITASTOR_VERSION=v3.0.0
+VITASTOR_VERSION=v3.0.15

 # Additional arguments for all containers
 # For example, you may want to specify a custom logging driver here
@@ -2,8 +2,7 @@

 set -e

-cp -urv /etc/default /host-etc/
-cp -urv /etc/systemd /host-etc/
-cp -urv /etc/udev /host-etc/
+cp -urv /etc/systemd/system/vitastor* /host-etc/systemd/system/
+cp -urv /etc/udev/rules.d /host-etc/udev/
 cp -urnv /etc/vitastor /host-etc/
 cp -urnv /opt/scripts/* /host-bin/
@@ -22,7 +22,6 @@ between clients, OSDs and etcd.
 - [rdma_max_msg](#rdma_max_msg)
 - [rdma_max_recv](#rdma_max_recv)
 - [rdma_max_send](#rdma_max_send)
- [rdma_odp](#rdma_odp)
 - [peer_connect_interval](#peer_connect_interval)
 - [peer_connect_timeout](#peer_connect_timeout)
 - [osd_idle_timeout](#osd_idle_timeout)
@@ -102,11 +101,6 @@ found or if `osd_network` is not specified. Auto-selection is also
 unsupported with old libibverbs < v32, like in Debian 10 Buster or
 CentOS 7.

-Vitastor supports all adapters, even ones without ODP support, like
-Mellanox ConnectX-3 and non-Mellanox cards. Versions up to Vitastor
-1.2.0 required ODP which is only present in Mellanox ConnectX >= 4.
-See also [rdma_odp](#rdma_odp).
-
 Run `ibv_devinfo -v` as root to list available RDMA devices and their
 features.

@@ -116,6 +110,23 @@ the manual of your network vendor for details about setting up the switch
 for RoCEv2 correctly. Usually it means setting up Lossless Ethernet with
 PFC (Priority Flow Control) and ECN (Explicit Congestion Notification).

+Vitastor supports all adapters, even ones without ODP (On-Demand Paging)
+support, like Mellanox ConnectX-3 and non-Mellanox cards. ODP is only present
+in Mellanox ConnectX >= 4 adapters and allows to skip memory registration
+for RDMA and thus, in theory, avoid memory copying.
+
+Versions up to Vitastor 1.2.0 required ODP, then it was disabled by default,
+but it was still supported up to 3.0.3. Now ODP support is removed because it
+actually only hurts performance: an example 3-node cluster with 8 NVMe in each
+node and 2*25 GBit/s ConnectX-6 RDMA network pushed 3950000 read iops without
+ODP, but only 239000 iops with ODP.
+
+This happens because Mellanox ODP implementation seems to be based on
+message retransmissions when the adapter doesn't know about the buffer yet -
+it likely uses standard "RNR retransmissions" (RNR = receiver not ready)
+which is generally slow in RDMA/RoCE networks. Here's a presentation about
+it from ISPASS-2021 conference: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
+
 ## rdma_port_num

 - Type: integer
@@ -187,28 +198,6 @@ less than `rdma_max_recv` so the receiving side doesn't run out of buffers.
 Doesn't affect memory usage - additional memory isn't allocated for send
 operations.

-## rdma_odp
-
- Type: boolean
- Default: false
-
-Use RDMA with On-Demand Paging. ODP is currently only available on Mellanox
-ConnectX-4 and newer adapters. ODP allows to not register memory explicitly
-for RDMA adapter to be able to use it. This, in turn, allows to skip memory
-copying during sending. One would think this should improve performance, but
-**in reality** RDMA performance with ODP is **drastically** worse. Example
-3-node cluster with 8 NVMe in each node and 2*25 GBit/s ConnectX-6 RDMA network
-without ODP pushes 3950000 read iops, but only 239000 iops with ODP...
-
-This happens because Mellanox ODP implementation seems to be based on
-message retransmissions when the adapter doesn't know about the buffer yet -
-it likely uses standard "RNR retransmissions" (RNR = receiver not ready)
-which is generally slow in RDMA/RoCE networks. Here's a presentation about
-it from ISPASS-2021 conference: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
-
-ODP support is retained in the code just in case a good ODP implementation
-appears one day.
-
 ## peer_connect_interval

 - Type: seconds
@@ -22,7 +22,6 @@
 - [rdma_max_msg](#rdma_max_msg)
 - [rdma_max_recv](#rdma_max_recv)
 - [rdma_max_send](#rdma_max_send)
- [rdma_odp](#rdma_odp)
 - [peer_connect_interval](#peer_connect_interval)
 - [peer_connect_timeout](#peer_connect_timeout)
 - [osd_idle_timeout](#osd_idle_timeout)
@@ -101,12 +100,6 @@ RoCEv1/RoCEv2, и даже позволяет полностью отключи
 не задана. Также автовыбор не поддерживается со старыми версиями библиотеки
 libibverbs < v32, например в Debian 10 Buster или CentOS 7.

-Vitastor поддерживает все модели адаптеров, включая те, у которых
-нет поддержки ODP, то есть вы можете использовать RDMA с ConnectX-3 и
-картами производства не Mellanox. Версии Vitastor до 1.2.0 включительно
-требовали ODP, который есть только на Mellanox ConnectX 4 и более новых.
-См. также [rdma_odp](#rdma_odp).
-
 Запустите `ibv_devinfo -v` от имени суперпользователя, чтобы посмотреть
 список доступных RDMA-устройств, их параметры и возможности.

@@ -117,6 +110,24 @@ Vitastor поддерживает все модели адаптеров, вкл
 подразумевает настройку сети без потерь на основе PFC (Priority Flow
 Control) и ECN (Explicit Congestion Notification).

+Vitastor поддерживает все модели адаптеров, включая те, у которых нет
+поддержки ODP (On-Demand Paging), например, ConnectX-3 и карты производства
+не Mellanox. Функция ODP доступна только на адаптерах Mellanox ConnectX-4 и
+более новых и позволяет не регистрировать память для её использования RDMA-картой,
+благодаря чему в теории можно избежать лишних копирований памяти.
+
+Версии Vitastor до 1.2.0 включительно требовали ODP, потом функция был отключена
+по умолчанию, но поддерживалась вплоть до версии 3.0.3. Сейчас поддержка ODP
+полностью удалена, так как на самом деле она только портит производительность:
+например, на 3-узловом кластере с 8 NVMe в каждом узле и сетью 2*25 Гбит/с на
+чтение с RDMA без ODP удаётся снять 3950000 iops, а с ODP - всего 239000 iops.
+
+Это происходит из-за того, что реализация ODP у Mellanox неоптимальная и
+основана на повторной передаче сообщений, когда карте не известен буфер -
+вероятно, на стандартных "RNR retransmission" (RNR = receiver not ready).
+А данные повторные передачи в RDMA/RoCE - всегда очень медленная штука.
+Презентация на эту тему с конференции ISPASS-2021: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
+
 ## rdma_port_num

 - Тип: целое число
@@ -192,29 +203,6 @@ OSD в любом случае согласовывают реальное зн
 Не влияет на потребление памяти - дополнительная память на операции отправки
 не выделяется.

-## rdma_odp
-
- Тип: булево (да/нет)
- Значение по умолчанию: false
-
-Использовать RDMA с On-Demand Paging. ODP - функция, доступная пока что
-исключительно на адаптерах Mellanox ConnectX-4 и более новых. ODP позволяет
-не регистрировать память для её использования RDMA-картой. Благодаря этому
-можно не копировать данные при отправке их в сеть и, казалось бы, это должно
-улучшать производительность - но **по факту** получается так, что
-производительность только ухудшается, причём сильно. Пример - на 3-узловом
-кластере с 8 NVMe в каждом узле и сетью 2*25 Гбит/с на чтение с RDMA без ODP
-удаётся снять 3950000 iops, а с ODP - всего 239000 iops...
-
-Это происходит из-за того, что реализация ODP у Mellanox неоптимальная и
-основана на повторной передаче сообщений, когда карте не известен буфер -
-вероятно, на стандартных "RNR retransmission" (RNR = receiver not ready).
-А данные повторные передачи в RDMA/RoCE - всегда очень медленная штука.
-Презентация на эту тему с конференции ISPASS-2021: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
-
-Возможность использования ODP сохранена в коде на случай, если вдруг в один
-прекрасный день появится хорошая реализация ODP.
-
 ## peer_connect_interval

 - Тип: секунды
@@ -38,6 +38,7 @@ with an OSD restart or, for some of them, even without restarting by updating co
 - [journal_io](#journal_io)
 - [journal_sector_buffer_count](#journal_sector_buffer_count)
 - [journal_no_same_sector_overwrites](#journal_no_same_sector_overwrites)
+- [skip_corrupted_meta_entries](#skip_corrupted_meta_entries)
 - [throttle_small_writes](#throttle_small_writes)
 - [throttle_target_iops](#throttle_target_iops)
 - [throttle_target_mbs](#throttle_target_mbs)
@@ -67,6 +68,9 @@ with an OSD restart or, for some of them, even without restarting by updating co
 - [pg_lock_retry_interval_ms](#pg_lock_retry_interval_ms)
 - [atomic_write_size](#atomic_write_size)
 - [use_atomic_flag](#use_atomic_flag)
+- [pg_reshard_chunk_size](#pg_reshard_chunk_size)
+- [pg_reshard_chunk_pause_ms](#pg_reshard_chunk_pause_ms)
+- [gc_on_start](#gc_on_start)

 ## bind_address

@@ -277,13 +281,19 @@ Maximum number of journal flushers (see above min_flusher_count).
 - Type: boolean
 - Default: true

-This parameter makes Vitastor always keep metadata area of the block device
-in memory. It's required for good performance because it allows to avoid
-additional read-modify-write cycles during metadata modifications. Metadata
-area size is currently roughly 224 MB per 1 TB of data. You can turn it off
-to reduce memory usage by this value, but it will hurt performance. This
-restriction is likely to be removed in the future along with the upgrade
-of the metadata storage scheme.
+Only for the old store ([meta_format](layout-osd.en.md#meta_format) 2).
+
+This parameter makes Vitastor keep a copy of metadata area in memory as it is
+on disk, in addition to the metadata database. When the option is enabled, every
+metadata entry is effectively stored in RAM twice. It's required for good performance
+because it allows to avoid additional read-modify-write cycles during metadata
+modifications. Metadata area size with the old store is roughly 224 MB per 1 TB
+of data. You can turn the option off to reduce memory usage by this value, but
+it will reduce performance.
+
+For the new store ([meta_format](layout-osd.en.md#meta_format) 3), the option
+may be changed in the future to support operation without loading full metadata
+database in memory.

 ## inmemory_journal

@@ -362,6 +372,8 @@ blocks. The only situation when you should increase it to a larger value
 is when you enable journal_no_same_sector_overwrites. In this case set
 it to, for example, 1024.

+Not applicable to the new store ([meta_format](layout-osd.en.md#meta_format) 3).
+
 ## journal_no_same_sector_overwrites

 - Type: boolean
@@ -375,6 +387,17 @@ journal after writing it instead of possibly overwriting it the second time.

 Most (99%) other SSDs don't need this option.

+Not applicable to the new store ([meta_format](layout-osd.en.md#meta_format) 3).
+
+## skip_corrupted_meta_entries
+
+- Type: boolean
+- Default: false
+
+Only for the new store ([meta_format](layout-osd.en.md#meta_format) 3).
+Allow OSD to start when some metadata entries or blocks are corrupted by
+skipping them. Should be only used as an emergency measure.
+
 ## throttle_small_writes

 - Type: boolean
@@ -682,7 +705,10 @@ with replicated pools and reach the best possible write performance.

 Default value is auto-detected during OSD initialization from
 `/sys/block/xx/queue/atomic_write_max_bytes` or assumed to be 4096 bytes
-because all known disks support 4 KB atomic writes.
+because all known disks support 4 KB atomic writes. Auto-detection is only used for
+NVMe disks because SAS disks require the explicit WRITE ATOMIC command which requires
+RWF_ATOMIC (see below [#use_atomic_flag]) but that flag works incorrectly in current
+Linux versions.

 You can also check if your NVMe drives support atomic writes by running
 the command `nvme id-ctrl /dev/nvme0n1 | grep awupf`. If the reported value,
@@ -697,12 +723,40 @@ reducing Write Amplification and improving write performance up to 2 times.

 - Type: boolean

-This option controls whether the Vitastor OSD uses RWF_ATOMIC write flag with atomic
-writes. This flag is only supported on Linux kernel since 6.11. Atomic writes are
-generally only safe to use with this flag because it tells the kernel to never fragment
-write requests and also to check the write against the actual atomic write capabilities
-of the device.
+This option controls whether Vitastor OSDs use RWF_ATOMIC write flag with atomic writes.
+This flag is supported since Linux 6.11 and adds some safety to atomic writes - the kernel
+guarantees to not fragment write requests with it and also to check them against the actual
+device atomic write capabilities.

-This option is enabled by default when atomic_write_size is set to a value larger than 4 KB.
-You can disable it if you're sure that your disks support atomic writes and you want to
-bypass the Linux atomic write checks.
+However, the option is disabled by default because the flag is currently UNUSABLE - Linux
+incorrectly requires writes with that flag to be of power-of-2 length and length-aligned.
+I.e., for example, 12 KB writes and not-8-KB aligned 8 KB writes are forbidden by the kernel,
+even though the NVMe specification allows them.
+
+For NVMe disks with `scheduler=none` writes aren't fragmented anyway so it's not a big deal.
+However, you can rebuild your kernel with [this patch](../../patches/linux-fix-atomic-write-checks.diff)
+and turn this option on. It will make your atomic writes a bit safer.
+
+## pg_reshard_chunk_size
+
+- Type: integer
+- Default: 100000
+
+Pool PG count change is a CPU-intensive operation because OSDs store the full object database
+in memory and have to move all entries between old and new PGs. Thus it's performed in chunks,
+with pauses between chunks to prevent blocking OSD's event loop and other clients' operations.
+This option sets the maximum number of object is a chunk. Moving 100k objects usually takes
+50-100ms. Chunk size equal to 0 means unlimited.
+
+## pg_reshard_chunk_pause_ms
+
+- Type: milliseconds
+- Default: 100
+
+This option sets the interval between handling two PG count change chunks.
+
+## gc_on_start
+
+- Type: boolean
+
+Forcibly clean all garbage entries in the new store on every OSD restart.
@@ -39,6 +39,7 @@
 - [journal_io](#journal_io)
 - [journal_sector_buffer_count](#journal_sector_buffer_count)
 - [journal_no_same_sector_overwrites](#journal_no_same_sector_overwrites)
+- [skip_corrupted_meta_entries](#skip_corrupted_meta_entries)
 - [throttle_small_writes](#throttle_small_writes)
 - [throttle_target_iops](#throttle_target_iops)
 - [throttle_target_mbs](#throttle_target_mbs)
@@ -68,6 +69,9 @@
 - [pg_lock_retry_interval_ms](#pg_lock_retry_interval_ms)
 - [atomic_write_size](#atomic_write_size)
 - [use_atomic_flag](#use_atomic_flag)
+- [pg_reshard_chunk_size](#pg_reshard_chunk_size)
+- [pg_reshard_chunk_pause_ms](#pg_reshard_chunk_pause_ms)
+- [gc_on_start](#gc_on_start)

 ## bind_address

@@ -285,13 +289,19 @@ Flusher - это микро-поток (корутина), которая коп
 - Тип: булево (да/нет)
 - Значение по умолчанию: true

-Данный параметр заставляет Vitastor всегда держать область метаданных диска
-в памяти. Это нужно, чтобы избегать дополнительных операций чтения с диска
-при записи. Размер области метаданных на данный момент составляет примерно
-224 МБ на 1 ТБ данных. При включении потребление памяти снизится примерно
-на эту величину, но при этом также снизится и производительность. В будущем,
-после обновления схемы хранения метаданных, это ограничение, скорее всего,
-будет ликвидировано.
+Только для старого хранилища ([meta_format](layout-osd.en.md#meta_format) 2).
+
+Данный параметр заставляет Vitastor всегда держать копию области метаданных
+в памяти в том же виде, как она лежит на диске, в дополнение к БД метаданных.
+То есть, с включённой опцией каждая запись метаданных хранится в памяти дважды.
+Это нужно, чтобы избегать дополнительных операций чтения с диска при записи.
+Размер области метаданных в старом хранилище составляет примерно 224 МБ на
+1 ТБ данных. Вы можете отключить опцию, чтобы снизить потребление памяти
+примерно на эту величину, но при этом также снизится и производительность.
+
+Для нового хранилища ([meta_format](layout-osd.en.md#meta_format) 3) опция,
+возможно, будет переработана в будущем для поддержки работы без полной
+загрузки метаданных в памяти.

 ## inmemory_journal

@@ -374,6 +384,8 @@ fsync небезопасным даже с режимом "directsync".
 нужно менять - это если вы включаете journal_no_same_sector_overwrites. В
 этом случае установите данный параметр, например, в 1024.

+Неприменимо к новому хранилищу ([meta_format](layout-osd.en.md#meta_format) 3).
+
 ## journal_no_same_sector_overwrites

 - Тип: булево (да/нет)
@@ -389,6 +401,18 @@ fsync небезопасным даже с режимом "directsync".

 Почти все другие SSD (99% моделей) не требуют данной опции.

+Неприменимо к новому хранилищу ([meta_format](layout-osd.en.md#meta_format) 3).
+
+## skip_corrupted_meta_entries
+
+- Тип: булево (да/нет)
+- Значение по умолчанию: false
+
+Только для нового хранилища ([meta_format](layout-osd.en.md#meta_format) 3).
+Разрешить OSD запускаться, даже если часть блоков или записей метаданных
+повреждена, пропуская их. Опция предназначена для использования только в
+целях аварийного восстановления.
+
 ## throttle_small_writes

 - Тип: булево (да/нет)
@@ -717,6 +741,9 @@ pg_minsize OSD во время переключений, что может по
 Значение по умолчанию авто-определяется во время инициализации OSD из
 `/sys/block/xx/queue/atomic_write_max_bytes` либо принимается равным 4096,
 так как все известные диски поддерживают атомарную запись 4 КБ блоков.
+Автоопределение применяется только для NVMe-дисков, так как SAS диски требуют
+использования отдельной команды WRITE ATOMIC, а для неё нужен флаг RWF_ATOMIC
+(см. ниже [#use_atomic_flag]), а он в текущих версиях Linux работает некорректно.

 Вы также можете проверить, поддерживают ли ваши NVMe-диски атомарную запись,
 с помощью команды `nvme id-ctrl /dev/nvme0n1 | grep awupf`. Если значение awupf
@@ -735,11 +762,41 @@ pg_minsize OSD во время переключений, что может по
 - Тип: булево (да/нет)

 Данная опция контролирует использование Vitastor OSD флага RWF_ATOMIC при атомарной записи
-блоков. Этот флаг поддерживается только в ядрах Linux начиная с 6.11. Атомарная запись
-является безопасной только при использовании этого флага, так как он сообщает ядру о том,
-что запрос записи нельзя фрагментировать и о том, что запрос нужно проверить на соответствие
-реальным возможностям атомарной записи устройства.
+блоков. Этот флаг поддерживается, начиная с версии ядра Linux 6.11 и добавляет немного корректности
+атомарным записям - ядро гарантирует отсутствие фрагментации запросов записи с этим флагом и
+проверяет их на соответствие реальным возможностям устройства.

-Опция включается по умолчанию, когда atomic_write_size устанавливается в значение больше 4 КБ.
-Вы можете явно отключить её, если уверены, что ваши диски поддерживают атомарную запись и
-хотите обойти проверки уровня ядра.
+Однако, данная опция по умолчанию отключена, так как флаг в текущих версиях Linux работает
+абсолютно НЕКОРРЕКТНО - при нём Linux требует, чтобы запросы записи имели длину, равную
+степени двойки и были выровнены на эту длину. То есть, например, 12 КБ запросы записи, а также
+8 КБ запросы записи по не-кратному 8 КБ смещению запрещаются ядром, хотя спецификация NVMe их
+разрешает.
+
+Для NVMe-дисков с `scheduler=none` запросы записи и так не фрагментируются, так что это не так
+уж и важно, однако вы можете пересобрать своё ядро с [этим патчем](../../patches/linux-fix-atomic-write-checks.diff)
+и включить данную опцию. Это сделает вашу атомарную запись капельку безопаснее.
+
+## pg_reshard_chunk_size
+
+- Тип: целое число
+- Значение по умолчанию: 100000
+
+Изменение числа PG в пуле заметно загружает процессор, так как OSD хранят полную базу данных
+объектов в памяти и им приходится перемещать все записи объектов между старыми и новыми PG.
+Поэтому изменение применяется порциями, с паузами между порциями, чтобы не блокировать обработку
+событий OSD и операции остальных клиентов. Данная опция задаёт максимальное число объектов
+в порции. Перемещение 100 тысяч объектов (значение по умолчанию) обычно занимает порядка
+50-100 миллисекунд. Значение опции 0 отключает лимит размера порции.
+
+## pg_reshard_chunk_pause_ms
+
+- Тип: миллисекунды
+- Значение по умолчанию: 100
+
+Данная опция задаёт интервал между обработкой двух порций изменения числа PG пулов.
+
+## gc_on_start
+
+- Тип: булево (да/нет)
+
+Принудительно очищать все мусорные записи в новом хранилище при каждом запуске OSD.
@@ -84,11 +84,6 @@
    unsupported with old libibverbs < v32, like in Debian 10 Buster or
    CentOS 7.

-    Vitastor supports all adapters, even ones without ODP support, like
-    Mellanox ConnectX-3 and non-Mellanox cards. Versions up to Vitastor
-    1.2.0 required ODP which is only present in Mellanox ConnectX >= 4.
-    See also [rdma_odp](#rdma_odp).
-
    Run `ibv_devinfo -v` as root to list available RDMA devices and their
    features.

@@ -97,6 +92,23 @@
    the manual of your network vendor for details about setting up the switch
    for RoCEv2 correctly. Usually it means setting up Lossless Ethernet with
    PFC (Priority Flow Control) and ECN (Explicit Congestion Notification).
+
+    Vitastor supports all adapters, even ones without ODP (On-Demand Paging)
+    support, like Mellanox ConnectX-3 and non-Mellanox cards. ODP is only present
+    in Mellanox ConnectX >= 4 adapters and allows to skip memory registration
+    for RDMA and thus, in theory, avoid memory copying.
+
+    Versions up to Vitastor 1.2.0 required ODP, then it was disabled by default,
+    but it was still supported up to 3.0.3. Now ODP support is removed because it
+    actually only hurts performance: an example 3-node cluster with 8 NVMe in each
+    node and 2*25 GBit/s ConnectX-6 RDMA network pushed 3950000 read iops without
+    ODP, but only 239000 iops with ODP.
+
+    This happens because Mellanox ODP implementation seems to be based on
+    message retransmissions when the adapter doesn't know about the buffer yet -
+    it likely uses standard "RNR retransmissions" (RNR = receiver not ready)
+    which is generally slow in RDMA/RoCE networks. Here's a presentation about
+    it from ISPASS-2021 conference: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
  info_ru: |
    Название RDMA-устройства для связи с Vitastor OSD (например, "rocep5s0f0").
    Если не указано, Vitastor попробует найти RoCE-устройство, соответствующее
@@ -105,12 +117,6 @@
    не задана. Также автовыбор не поддерживается со старыми версиями библиотеки
    libibverbs < v32, например в Debian 10 Buster или CentOS 7.

-    Vitastor поддерживает все модели адаптеров, включая те, у которых
-    нет поддержки ODP, то есть вы можете использовать RDMA с ConnectX-3 и
-    картами производства не Mellanox. Версии Vitastor до 1.2.0 включительно
-    требовали ODP, который есть только на Mellanox ConnectX 4 и более новых.
-    См. также [rdma_odp](#rdma_odp).
-
    Запустите `ibv_devinfo -v` от имени суперпользователя, чтобы посмотреть
    список доступных RDMA-устройств, их параметры и возможности.

@@ -120,6 +126,24 @@
    коммутатора для RoCEv2 ищите в документации производителя. Обычно это
    подразумевает настройку сети без потерь на основе PFC (Priority Flow
    Control) и ECN (Explicit Congestion Notification).
+
+    Vitastor поддерживает все модели адаптеров, включая те, у которых нет
+    поддержки ODP (On-Demand Paging), например, ConnectX-3 и карты производства
+    не Mellanox. Функция ODP доступна только на адаптерах Mellanox ConnectX-4 и
+    более новых и позволяет не регистрировать память для её использования RDMA-картой,
+    благодаря чему в теории можно избежать лишних копирований памяти.
+
+    Версии Vitastor до 1.2.0 включительно требовали ODP, потом функция был отключена
+    по умолчанию, но поддерживалась вплоть до версии 3.0.3. Сейчас поддержка ODP
+    полностью удалена, так как на самом деле она только портит производительность:
+    например, на 3-узловом кластере с 8 NVMe в каждом узле и сетью 2*25 Гбит/с на
+    чтение с RDMA без ODP удаётся снять 3950000 iops, а с ODP - всего 239000 iops.
+
+    Это происходит из-за того, что реализация ODP у Mellanox неоптимальная и
+    основана на повторной передаче сообщений, когда карте не известен буфер -
+    вероятно, на стандартных "RNR retransmission" (RNR = receiver not ready).
+    А данные повторные передачи в RDMA/RoCE - всегда очень медленная штука.
+    Презентация на эту тему с конференции ISPASS-2021: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
 - name: rdma_port_num
  type: int
  info: |
@@ -218,45 +242,6 @@
    у принимающей стороны в процессе работы не заканчивались буферы на приём.
    Не влияет на потребление памяти - дополнительная память на операции отправки
    не выделяется.
- name: rdma_odp
-  type: bool
-  default: false
-  online: false
-  info: |
-    Use RDMA with On-Demand Paging. ODP is currently only available on Mellanox
-    ConnectX-4 and newer adapters. ODP allows to not register memory explicitly
-    for RDMA adapter to be able to use it. This, in turn, allows to skip memory
-    copying during sending. One would think this should improve performance, but
-    **in reality** RDMA performance with ODP is **drastically** worse. Example
-    3-node cluster with 8 NVMe in each node and 2*25 GBit/s ConnectX-6 RDMA network
-    without ODP pushes 3950000 read iops, but only 239000 iops with ODP...
-
-    This happens because Mellanox ODP implementation seems to be based on
-    message retransmissions when the adapter doesn't know about the buffer yet -
-    it likely uses standard "RNR retransmissions" (RNR = receiver not ready)
-    which is generally slow in RDMA/RoCE networks. Here's a presentation about
-    it from ISPASS-2021 conference: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
-
-    ODP support is retained in the code just in case a good ODP implementation
-    appears one day.
-  info_ru: |
-    Использовать RDMA с On-Demand Paging. ODP - функция, доступная пока что
-    исключительно на адаптерах Mellanox ConnectX-4 и более новых. ODP позволяет
-    не регистрировать память для её использования RDMA-картой. Благодаря этому
-    можно не копировать данные при отправке их в сеть и, казалось бы, это должно
-    улучшать производительность - но **по факту** получается так, что
-    производительность только ухудшается, причём сильно. Пример - на 3-узловом
-    кластере с 8 NVMe в каждом узле и сетью 2*25 Гбит/с на чтение с RDMA без ODP
-    удаётся снять 3950000 iops, а с ODP - всего 239000 iops...
-
-    Это происходит из-за того, что реализация ODP у Mellanox неоптимальная и
-    основана на повторной передаче сообщений, когда карте не известен буфер -
-    вероятно, на стандартных "RNR retransmission" (RNR = receiver not ready).
-    А данные повторные передачи в RDMA/RoCE - всегда очень медленная штука.
-    Презентация на эту тему с конференции ISPASS-2021: https://tkygtr6.github.io/pub/ISPASS21_slides.pdf
-
-    Возможность использования ODP сохранена в коде на случай, если вдруг в один
-    прекрасный день появится хорошая реализация ODP.
 - name: peer_connect_interval
  type: sec
  min: 1
@@ -253,21 +253,33 @@
  type: bool
  default: true
  info: |
-    This parameter makes Vitastor always keep metadata area of the block device
-    in memory. It's required for good performance because it allows to avoid
-    additional read-modify-write cycles during metadata modifications. Metadata
-    area size is currently roughly 224 MB per 1 TB of data. You can turn it off
-    to reduce memory usage by this value, but it will hurt performance. This
-    restriction is likely to be removed in the future along with the upgrade
-    of the metadata storage scheme.
+    Only for the old store ([meta_format](layout-osd.en.md#meta_format) 2).
+
+    This parameter makes Vitastor keep a copy of metadata area in memory as it is
+    on disk, in addition to the metadata database. When the option is enabled, every
+    metadata entry is effectively stored in RAM twice. It's required for good performance
+    because it allows to avoid additional read-modify-write cycles during metadata
+    modifications. Metadata area size with the old store is roughly 224 MB per 1 TB
+    of data. You can turn the option off to reduce memory usage by this value, but
+    it will reduce performance.
+
+    For the new store ([meta_format](layout-osd.en.md#meta_format) 3), the option
+    may be changed in the future to support operation without loading full metadata
+    database in memory.
  info_ru: |
-    Данный параметр заставляет Vitastor всегда держать область метаданных диска
-    в памяти. Это нужно, чтобы избегать дополнительных операций чтения с диска
-    при записи. Размер области метаданных на данный момент составляет примерно
-    224 МБ на 1 ТБ данных. При включении потребление памяти снизится примерно
-    на эту величину, но при этом также снизится и производительность. В будущем,
-    после обновления схемы хранения метаданных, это ограничение, скорее всего,
-    будет ликвидировано.
+    Только для старого хранилища ([meta_format](layout-osd.en.md#meta_format) 2).
+
+    Данный параметр заставляет Vitastor всегда держать копию области метаданных
+    в памяти в том же виде, как она лежит на диске, в дополнение к БД метаданных.
+    То есть, с включённой опцией каждая запись метаданных хранится в памяти дважды.
+    Это нужно, чтобы избегать дополнительных операций чтения с диска при записи.
+    Размер области метаданных в старом хранилище составляет примерно 224 МБ на
+    1 ТБ данных. Вы можете отключить опцию, чтобы снизить потребление памяти
+    примерно на эту величину, но при этом также снизится и производительность.
+
+    Для нового хранилища ([meta_format](layout-osd.en.md#meta_format) 3) опция,
+    возможно, будет переработана в будущем для поддержки работы без полной
+    загрузки метаданных в памяти.
 - name: inmemory_journal
  type: bool
  default: true
@@ -386,11 +398,15 @@
    blocks. The only situation when you should increase it to a larger value
    is when you enable journal_no_same_sector_overwrites. In this case set
    it to, for example, 1024.
+
+    Not applicable to the new store ([meta_format](layout-osd.en.md#meta_format) 3).
  info_ru: |
    Максимальное число буферов, разрешённых для использования под записываемые
    в журнал блоки метаданных. Единственная ситуация, в которой этот параметр
    нужно менять - это если вы включаете journal_no_same_sector_overwrites. В
    этом случае установите данный параметр, например, в 1024.
+
+    Неприменимо к новому хранилищу ([meta_format](layout-osd.en.md#meta_format) 3).
 - name: journal_no_same_sector_overwrites
  type: bool
  default: false
@@ -402,6 +418,8 @@
    journal after writing it instead of possibly overwriting it the second time.

    Most (99%) other SSDs don't need this option.
+
+    Not applicable to the new store ([meta_format](layout-osd.en.md#meta_format) 3).
  info_ru: |
    Включайте данную опцию для SSD вроде Intel D3-S4510 и D3-S4610, которые
    ОЧЕНЬ не любят, когда ПО перезаписывает один и тот же сектор несколько раз
@@ -412,6 +430,20 @@
    самого сектора.

    Почти все другие SSD (99% моделей) не требуют данной опции.
+
+    Неприменимо к новому хранилищу ([meta_format](layout-osd.en.md#meta_format) 3).
+- name: skip_corrupted_meta_entries
+  type: bool
+  default: false
+  info: |
+    Only for the new store ([meta_format](layout-osd.en.md#meta_format) 3).
+    Allow OSD to start when some metadata entries or blocks are corrupted by
+    skipping them. Should be only used as an emergency measure.
+  info_ru: |
+    Только для нового хранилища ([meta_format](layout-osd.en.md#meta_format) 3).
+    Разрешить OSD запускаться, даже если часть блоков или записей метаданных
+    повреждена, пропуская их. Опция предназначена для использования только в
+    целях аварийного восстановления.
 - name: throttle_small_writes
  type: bool
  default: false
@@ -813,7 +845,10 @@

    Default value is auto-detected during OSD initialization from
    `/sys/block/xx/queue/atomic_write_max_bytes` or assumed to be 4096 bytes
-    because all known disks support 4 KB atomic writes.
+    because all known disks support 4 KB atomic writes. Auto-detection is only used for
+    NVMe disks because SAS disks require the explicit WRITE ATOMIC command which requires
+    RWF_ATOMIC (see below [#use_atomic_flag]) but that flag works incorrectly in current
+    Linux versions.

    You can also check if your NVMe drives support atomic writes by running
    the command `nvme id-ctrl /dev/nvme0n1 | grep awupf`. If the reported value,
@@ -834,6 +869,9 @@
    Значение по умолчанию авто-определяется во время инициализации OSD из
    `/sys/block/xx/queue/atomic_write_max_bytes` либо принимается равным 4096,
    так как все известные диски поддерживают атомарную запись 4 КБ блоков.
+    Автоопределение применяется только для NVMe-дисков, так как SAS диски требуют
+    использования отдельной команды WRITE ATOMIC, а для неё нужен флаг RWF_ATOMIC
+    (см. ниже [#use_atomic_flag]), а он в текущих версиях Linux работает некорректно.

    Вы также можете проверить, поддерживают ли ваши NVMe-диски атомарную запись,
    с помощью команды `nvme id-ctrl /dev/nvme0n1 | grep awupf`. Если значение awupf
@@ -849,22 +887,58 @@
 - name: use_atomic_flag
  type: bool
  info: |
-    This option controls whether the Vitastor OSD uses RWF_ATOMIC write flag with atomic
-    writes. This flag is only supported on Linux kernel since 6.11. Atomic writes are
-    generally only safe to use with this flag because it tells the kernel to never fragment
-    write requests and also to check the write against the actual atomic write capabilities
-    of the device.
+    This option controls whether Vitastor OSDs use RWF_ATOMIC write flag with atomic writes.
+    This flag is supported since Linux 6.11 and adds some safety to atomic writes - the kernel
+    guarantees to not fragment write requests with it and also to check them against the actual
+    device atomic write capabilities.

-    This option is enabled by default when atomic_write_size is set to a value larger than 4 KB.
-    You can disable it if you're sure that your disks support atomic writes and you want to
-    bypass the Linux atomic write checks.
+    However, the option is disabled by default because the flag is currently UNUSABLE - Linux
+    incorrectly requires writes with that flag to be of power-of-2 length and length-aligned.
+    I.e., for example, 12 KB writes and not-8-KB aligned 8 KB writes are forbidden by the kernel,
+    even though the NVMe specification allows them.
+
+    For NVMe disks with `scheduler=none` writes aren't fragmented anyway so it's not a big deal.
+    However, you can rebuild your kernel with [this patch](../../patches/linux-fix-atomic-write-checks.diff)
+    and turn this option on. It will make your atomic writes a bit safer.
  info_ru: |
    Данная опция контролирует использование Vitastor OSD флага RWF_ATOMIC при атомарной записи
-    блоков. Этот флаг поддерживается только в ядрах Linux начиная с 6.11. Атомарная запись
-    является безопасной только при использовании этого флага, так как он сообщает ядру о том,
-    что запрос записи нельзя фрагментировать и о том, что запрос нужно проверить на соответствие
-    реальным возможностям атомарной записи устройства.
+    блоков. Этот флаг поддерживается, начиная с версии ядра Linux 6.11 и добавляет немного корректности
+    атомарным записям - ядро гарантирует отсутствие фрагментации запросов записи с этим флагом и
+    проверяет их на соответствие реальным возможностям устройства.

-    Опция включается по умолчанию, когда atomic_write_size устанавливается в значение больше 4 КБ.
-    Вы можете явно отключить её, если уверены, что ваши диски поддерживают атомарную запись и
-    хотите обойти проверки уровня ядра.
+    Однако, данная опция по умолчанию отключена, так как флаг в текущих версиях Linux работает
+    абсолютно НЕКОРРЕКТНО - при нём Linux требует, чтобы запросы записи имели длину, равную
+    степени двойки и были выровнены на эту длину. То есть, например, 12 КБ запросы записи, а также
+    8 КБ запросы записи по не-кратному 8 КБ смещению запрещаются ядром, хотя спецификация NVMe их
+    разрешает.
+
+    Для NVMe-дисков с `scheduler=none` запросы записи и так не фрагментируются, так что это не так
+    уж и важно, однако вы можете пересобрать своё ядро с [этим патчем](../../patches/linux-fix-atomic-write-checks.diff)
+    и включить данную опцию. Это сделает вашу атомарную запись капельку безопаснее.
+- name: pg_reshard_chunk_size
+  type: int
+  default: 100000
+  info: |
+    Pool PG count change is a CPU-intensive operation because OSDs store the full object database
+    in memory and have to move all entries between old and new PGs. Thus it's performed in chunks,
+    with pauses between chunks to prevent blocking OSD's event loop and other clients' operations.
+    This option sets the maximum number of object is a chunk. Moving 100k objects usually takes
+    50-100ms. Chunk size equal to 0 means unlimited.
+  info_ru: |
+    Изменение числа PG в пуле заметно загружает процессор, так как OSD хранят полную базу данных
+    объектов в памяти и им приходится перемещать все записи объектов между старыми и новыми PG.
+    Поэтому изменение применяется порциями, с паузами между порциями, чтобы не блокировать обработку
+    событий OSD и операции остальных клиентов. Данная опция задаёт максимальное число объектов
+    в порции. Перемещение 100 тысяч объектов (значение по умолчанию) обычно занимает порядка
+    50-100 миллисекунд. Значение опции 0 отключает лимит размера порции.
+- name: pg_reshard_chunk_pause_ms
+  type: ms
+  default: 100
+  info: |
+    This option sets the interval between handling two PG count change chunks.
+  info_ru: |
+    Данная опция задаёт интервал между обработкой двух порций изменения числа PG пулов.
+- name: gc_on_start
+  type: bool
+  info: Forcibly clean all garbage entries in the new store on every OSD restart.
+  info_ru: Принудительно очищать все мусорные записи в новом хранилище при каждом запуске OSD.
@@ -26,13 +26,37 @@ at Vitastor Kubernetes operator: https://github.com/Antilles7227/vitastor-operat
 The instruction is very simple.

 1. Download a Docker image of the desired version: \
-   `docker pull vitalif/vitastor:v3.0.0`
+   `docker pull vitalif/vitastor:v3.0.15`
 2. Install scripts to the host system: \
-   `docker run --rm -it -v /etc:/host-etc -v /usr/bin:/host-bin vitalif/vitastor:v3.0.0 install.sh`
+   `docker run --rm -it -v /etc:/host-etc -v /usr/bin:/host-bin vitalif/vitastor:v3.0.15 install.sh`
 3. Reload udev rules: \
   `udevadm control --reload-rules`
+4. Enable the vitastor-host service: \
+   `systemctl enable --now vitastor-host`

-And you can return to [Quick Start](../intro/quickstart.en.md).
+After these steps, you can return to [Quick Start](../intro/quickstart.en.md).
+
+## Podman
+
+If you use Podman, run the following commands as root before installing Vitastor containers:
+
+```
+ln -s podman /usr/bin/docker
+
+mkdir -p /etc/systemd/system/systemd-udevd.service.d
+
+cat >/etc/systemd/system/systemd-udevd.service.d/override.conf <<EOF
+[Service]
+CapabilityBoundingSet=~
+SystemCallFilter=@mount capset
+EOF
+
+systemctl daemon-reload
+
+systemctl restart systemd-udevd
+```
+
+Without it, udev fails to do calls into a Podman container and Vitastor disk detection doesn't work.

 ## Upgrading Containers

@@ -25,14 +25,39 @@ Vitastor можно установить в Docker/Podman. При этом etcd,
 Инструкция по установке максимально простая.

 1. Скачайте Docker-образ желаемой версии: \
-   `docker pull vitalif/vitastor:v3.0.0`
+   `docker pull vitalif/vitastor:v3.0.15`
 2. Установите скрипты в хост-систему командой: \
-   `docker run --rm -it -v /etc:/host-etc -v /usr/bin:/host-bin vitalif/vitastor:v3.0.0 install.sh`
+   `docker run --rm -it -v /etc:/host-etc -v /usr/bin:/host-bin vitalif/vitastor:v3.0.15 install.sh`
 3. Перезагрузите правила udev: \
   `udevadm control --reload-rules`
+4. Включите сервис vitastor-host: \
+   `systemctl enable --now vitastor-host`

 После этого вы можете возвращаться к разделу [Быстрый старт](../intro/quickstart.ru.md).

+## Podman
+
+Если вы используете Podman, перед установкой контейнеров Vitastor выполните следующие
+команды от имени суперпользователя:
+
+```
+ln -s podman /usr/bin/docker
+
+mkdir -p /etc/systemd/system/systemd-udevd.service.d
+
+cat >/etc/systemd/system/systemd-udevd.service.d/override.conf <<EOF
+[Service]
+CapabilityBoundingSet=~
+SystemCallFilter=@mount capset
+EOF
+
+systemctl daemon-reload
+
+systemctl restart systemd-udevd
+```
+
+Без этих настроек udev не может делать вызовы внутрь Podman-контейнеров и определение дисков Vitastor не работает.
+
 ## Обновление контейнеров

 Сначала обязательно проверьте раздел [Обновление Vitastor](../usage/admin.ru.md#обновление-vitastor),
@@ -17,6 +17,7 @@
  - Debian 10 (Buster): `deb https://vitastor.io/debian buster main`
  - Ubuntu 22.04 (Jammy): `deb https://vitastor.io/debian jammy main`
  - Ubuntu 24.04 (Noble): `deb https://vitastor.io/debian noble main`
+  - Ubuntu 26.04 (Resolute): `deb https://vitastor.io/debian resolute main`
  - Add `-oldstable` to bookworm/bullseye/buster in this line to install the last
    stable version from 0.9.x branch instead of 1.x
 - To always prefer vitastor-patched QEMU and Libvirt versions, add the following to `/etc/apt/preferences`:
@@ -33,15 +34,17 @@
  - CentOS 7: `yum install https://vitastor.io/rpms/centos/7/vitastor-release.rpm`
  - CentOS 8: `dnf install https://vitastor.io/rpms/centos/8/vitastor-release.rpm`
  - AlmaLinux 9 and other RHEL 9 clones (Rocky, Oracle...): `dnf install https://vitastor.io/rpms/centos/9/vitastor-release.rpm`
+  - AlmaLinux 10 and other RHEL 10 clones: `dnf install https://vitastor.io/rpms/centos/10/vitastor-release.rpm`
 - Enable EPEL: `yum/dnf install epel-release`
 - Enable additional CentOS repositories:
  - CentOS 7: `yum install centos-release-scl`
  - CentOS 8: `dnf install centos-release-advanced-virtualization`
-  - RHEL 9 clones: not required
+  - RHEL 9/10 clones: not required
 - Enable elrepo-kernel:
  - CentOS 7: `yum install https://www.elrepo.org/elrepo-release-7.el7.elrepo.noarch.rpm`
  - CentOS 8: `dnf install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm`
  - RHEL 9 clones: `dnf install https://www.elrepo.org/elrepo-release-9.el9.elrepo.noarch.rpm`
+  - RHEL 10 clones: not required
 - Install packages: `yum/dnf install vitastor lpsolve etcd kernel-ml qemu-kvm`

 ## Installation requirements
@@ -17,6 +17,7 @@
  - Debian 10 (Buster): `deb https://vitastor.io/debian buster main`
  - Ubuntu 22.04 (Jammy): `deb https://vitastor.io/debian jammy main`
  - Ubuntu 24.04 (Noble): `deb https://vitastor.io/debian noble main`
+  - Ubuntu 26.04 (Resolute): `deb https://vitastor.io/debian resolute main`
  - Добавьте `-oldstable` к слову bookworm/bullseye/buster в этой строке, чтобы
    установить последнюю стабильную версию из ветки 0.9.x вместо 1.x
 - Чтобы всегда предпочитались версии пакетов QEMU и Libvirt с патчами Vitastor, добавьте в `/etc/apt/preferences`:
@@ -33,15 +34,17 @@
  - CentOS 7: `yum install https://vitastor.io/rpms/centos/7/vitastor-release.rpm`
  - CentOS 8: `dnf install https://vitastor.io/rpms/centos/8/vitastor-release.rpm`
  - AlmaLinux 9 и другие клоны RHEL 9 (Rocky, Oracle...): `dnf install https://vitastor.io/rpms/centos/9/vitastor-release.rpm`
+  - AlmaLinux 10 и другие клоны RHEL 10: `dnf install https://vitastor.io/rpms/centos/10/vitastor-release.rpm`
 - Включите EPEL: `yum/dnf install epel-release`
 - Включите дополнительные репозитории CentOS:
  - CentOS 7: `yum install centos-release-scl`
  - CentOS 8: `dnf install centos-release-advanced-virtualization`
-  - Клоны RHEL 9: не нужно
+  - Клоны RHEL 9/10: не нужно
 - Включите elrepo-kernel:
  - CentOS 7: `yum install https://www.elrepo.org/elrepo-release-7.el7.elrepo.noarch.rpm`
  - CentOS 8: `dnf install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm`
  - Клоны RHEL 9: `dnf install https://www.elrepo.org/elrepo-release-9.el9.elrepo.noarch.rpm`
+  - Клоны RHEL 10: не нужно
 - Установите пакеты: `yum/dnf install vitastor lpsolve etcd kernel-ml qemu-kvm`

 ## Установочные требования
@@ -6,7 +6,7 @@

 # Proxmox VE

-To enable Vitastor support in Proxmox Virtual Environment (6.4-8.x are supported):
+To enable Vitastor support in Proxmox Virtual Environment (6.4-9.x are supported):

 - Add the corresponding Vitastor Debian repository into sources.list on Proxmox hosts:
  trixie for 9.0+, bookworm for 8.1+, pve8.0 for 8.0, bullseye for 7.4, pve7.3 for 7.3, pve7.2 for 7.2, pve7.1 for 7.1, buster for 6.4
@@ -6,7 +6,7 @@

 # Proxmox VE

-Чтобы подключить Vitastor к Proxmox Virtual Environment (поддерживаются версии 6.4-8.x):
+Чтобы подключить Vitastor к Proxmox Virtual Environment (поддерживаются версии 6.4-9.x):

 - Добавьте соответствующий Debian-репозиторий Vitastor в sources.list на хостах Proxmox:
  trixie для 9.0+, bookworm для 8.1+, pve8.0 для 8.0, bullseye для 7.4, pve7.3 для 7.3, pve7.2 для 7.2, pve7.1 для 7.1, buster для 6.4
@@ -16,8 +16,7 @@
  designated initializers support from C++20
 - CMake
 - jerasure headers and libraries
- ISA-L, libibverbs and librdmacm headers and libraries (optional)
- tcmalloc (google-perftools-dev)
+- ISA-L, libibverbs, librdmacm, libnl3 headers and libraries (optional)

 ## Basic instructions

@@ -16,8 +16,7 @@
  назначенных инициализаторов (designated initializers) из C++20
 - CMake
 - Заголовки и библиотеки jerasure
- Опционально - заголовки и библиотеки ISA-L, libibverbs, librdmacm
- tcmalloc (google-perftools-dev)
+- Опционально - заголовки и библиотеки ISA-L, libibverbs, librdmacm, libnl3

 ## Базовая инструкция

@@ -95,6 +95,8 @@ Options (single-device mode):
 Options (both modes):

 ```
+--tags tag1,tag2           Set new OSD tag(s)
+--weight <number>          Set new OSD weight (between 0 to 1)
 --journal_size 1G/32M      Set journal size (area or partition size)
 --block_size 1M/128k       Set blockstore object size
 --bitmap_granularity 4k    Set bitmap granularity
@@ -96,6 +96,8 @@ vitastor-disk - инструмент командной строки для уп
 Опции для обоих режимов:

 ```
+--tags tag1,tag2           Задать теги для новых OSD
+--weight <number>          Задать вес для новых OSD (от 0 до 1)
 --journal_size 1G/32M      Задать размер журнала (области или раздела журнала)
 --block_size 1M/128k       Задать размер объекта хранилища
 --bitmap_granularity 4k    Задать гранулярность битовых карт
@@ -262,3 +262,4 @@ Options:
 | `--logfile <FILE>` | log to the specified file                                |
 | `--enforce 1`      | enforce permissions at the server side (no by default)   |
 | `--foreground 1`   | stay in foreground, do not daemonize                     |
+| `--trace`          | trace all NFS requests                                   |
@@ -274,3 +274,4 @@ VitastorFS из GPUDirect.
 | `--logfile <FILE>` | записывать логи в заданный файл                         |
 | `--enforce 1`      | проверять права доступа на стороне сервера (по умолчанию нет) |
 | `--foreground 1`   | не уходить в фон после запуска                          |
+| `--trace`          | логгировать все запросы NFS                             |
@@ -18,7 +18,7 @@ class AntiEtcdAdapter
                cluster = cluster ? (''+(cluster||'')).split(/,+/) : [];
            cluster = Object.keys(cluster.reduce((a, url) =>
            {
-                a[url.toLowerCase().replace(/^(https?:\/\/)/, '').replace(/\/.*$/, '')] = true;
+                a[url.toLowerCase().replace(/^(https?:\/\/)?(.*?)(\/.*)?$/, (m, m1, m2) => (m1||'http://')+m2)] = true;
                return a;
            }, {}));
            const cfg_port = config.antietcd_port;
@@ -26,7 +26,18 @@ class AntiEtcdAdapter
            is_local['0.0.0.0'] = true;
            is_local['::'] = true;
            is_local[''] = true;
-            const selected = cluster.map(s => s.split(':', 2)).filter(ip => is_local[ip[0]] && (!cfg_port || ip[1] == cfg_port));
+            // split :, 3 -> <schema>:<//ip>:<port>
+            const selected = [];
+            for (let i = 0; i < cluster.length; i++)
+            {
+                const m = /^(https?:\/\/)?(?:\[(.*)\]|([^\[\:]+))(?::(\d+))?$/.exec(cluster[i]);
+                if (!m)
+                    continue;
+                const ip = m[3] || m[2];
+                const port = m[4] || 2379;
+                if (is_local[ip] && (!cfg_port || port == cfg_port))
+                    selected.push({ idx: i, ip, port });
+            }
            if (selected.length > 1)
            {
                console.error('More than 1 etcd_address matches local IPs, please specify port');
@@ -35,15 +46,16 @@ class AntiEtcdAdapter
            else if (selected.length == 1)
            {
                const antietcd_config = {
-                    ip: selected[0][0],
-                    port: selected[0][1],
-                    data: config.antietcd_data_file || ((config.antietcd_data_dir || '/var/lib/vitastor') + '/mon_'+selected[0][1]+'.json.gz'),
+                    ip: selected[0].ip,
+                    port: selected[0].port,
+                    data: config.antietcd_data_file || ((config.antietcd_data_dir || '/var/lib/vitastor') + '/mon_'+selected[0].port+'.json.gz'),
                    persist_filter: vitastor_persist_filter({ vitastor_prefix: config.etcd_prefix || '/vitastor' }),
-                    node_id: selected[0][0]+':'+selected[0][1], // node_id = ip:port
-                    cluster: (cluster.length == 1 ? null : cluster.reduce((a, c) => { a[c] = "http://"+c; return a; }, {})),
+                    node_id: cluster[selected[0].idx].replace(/^(https?:\/\/)/, ''), // same as in <cluster> below
+                    cluster: (cluster.length == 1 ? null : cluster.reduce((a, c) => { a[c.replace(/^(https?:\/\/)/, '')] = c; return a; }, {})),
                    cluster_key: (config.etcd_prefix || '/vitastor'),
                    stale_read: 1,
                    log_level: 1,
+                    logs: { cluster: true },
                };
                for (const key in config)
                {
@@ -16,7 +16,7 @@ async function create_http_server(cfg, handler)
        };
        if (cfg.mon_https_ca)
        {
-            tls.mon_https_ca = await fsp.readFile(cfg.mon_https_ca);
+            tls.ca = await fsp.readFile(cfg.mon_https_ca);
        }
        if (cfg.mon_https_client_auth)
        {
@@ -10,16 +10,19 @@ const NO_OSD = 'Z';
 async function lp_solve(text)
 {
    const cp = child_process.spawn('lp_solve');
-    let stdout = '', stderr = '', finish_cb;
+    let stdout = '', stderr = '', finish_cb, finished = 0;
    cp.stdout.on('data', buf => stdout += buf.toString());
    cp.stderr.on('data', buf => stderr += buf.toString());
-    cp.on('exit', () => finish_cb && finish_cb());
+    cp.stdout.on('end', () => finish_cb());
+    cp.stderr.on('end', () => finish_cb());
    cp.stdin.write(text);
    cp.stdin.end();
-    if (cp.exitCode == null)
+    await new Promise(ok => (finish_cb = () =>
    {
-        await new Promise(ok => finish_cb = ok);
-    }
+        finished++;
+        if (finished == 2)
+            ok();
+    }));
    if (!stdout.trim())
    {
        return null;
@@ -109,9 +112,10 @@ function make_cyclic(pgs, parity_space)
 {
    if (parity_space > 1)
    {
-        for (const pg in pgs)
+        for (const id in pgs)
        {
-            for (let i = 1; i < pg.size; i++)
+            const pg = pgs[id];
+            for (let i = 1; i < pg.length; i++)
            {
                const cyclic = [ ...pg.slice(i), ...pg.slice(0, i) ];
                pgs['pg_'+cyclic.join('_')] = cyclic;
@@ -627,7 +627,7 @@ class Mon
                if (this.state.pg.history[pool_id] &&
                    this.state.pg.history[pool_id][pg])
                {
-                    pg_history[pg-1] = this.state.pg.history[pool_id][pg];
+                    pg_history[pg-1] = JSON.parse(JSON.stringify(this.state.pg.history[pool_id][pg]));
                }
            }
            const real_prev_pgs = [];
@@ -719,7 +719,7 @@ class Mon
                this.next_recheck_timer = null;
                this.next_recheck_at = 0;
                this.schedule_recheck();
-            }, now-this.next_recheck_at);
+            }, (this.next_recheck_at-now)*1000);
        }
    }

@@ -87,7 +87,7 @@ function make_hier_tree(global_config, tree)
    tree[''] = { children: [] };
    for (const node_id in tree)
    {
-        if (node_id === '' || !(tree[node_id].children||[]).length && (tree[node_id].size||0) <= 0)
+        if (node_id === '')
        {
            continue;
        }
@@ -1,6 +1,6 @@
 {
  "name": "vitastor-mon",
-  "version": "3.0.0",
+  "version": "3.0.15",
  "description": "Vitastor SDS monitor service",
  "main": "mon-main.js",
  "scripts": {
@@ -9,7 +9,7 @@
  "author": "Vitaliy Filippov",
  "license": "UNLICENSED",
  "dependencies": {
-    "antietcd": "^1.1.3",
+    "antietcd": "^1.3.1",
    "sprintf-js": "^1.1.2",
    "ws": "^7.2.5"
  },
@@ -52,6 +52,7 @@ function recheck_primary(state, global_config, up_osds, osd_tree)
            continue;
        }
        const aff_osds = get_affinity_osds(pool_cfg, up_osds, osd_tree);
+        let paused = false;
        for (let pg_num = 1; pg_num <= pool_cfg.pg_count; pg_num++)
        {
            if (!state.pg.config.items[pool_id])
@@ -74,6 +75,19 @@ function recheck_primary(state, global_config, up_osds, osd_tree)
                    );
                    new_pg_config.items[pool_id][pg_num].primary = new_primary;
                }
+                paused = paused || !!pg_cfg.pause;
+            }
+        }
+        if (paused)
+        {
+            if (!new_pg_config)
+            {
+                new_pg_config = JSON.parse(JSON.stringify(state.pg.config));
+            }
+            console.log(`Resuming paused pool ${pool_id}`);
+            for (const pg in new_pg_config.items[pool_id])
+            {
+                delete new_pg_config.items[pool_id][pg].pause;
            }
        }
    }
@@ -178,10 +192,10 @@ async function generate_pool_pgs(state, global_config, pool_id, osd_tree, levels
    const rules = use_rules ? get_pg_rules(pool_id, pool_cfg, global_config.placement_levels) : null;
    const folded = fold_failure_domains(Object.values(pool_tree), use_rules ? rules : [ [ [ pool_cfg.failure_domain ] ] ]);
    // FIXME: Remove/merge make_hier_tree() step somewhere, however it's needed to remove empty nodes
-    const folded_tree = make_hier_tree(global_config, folded.nodes);
+    const folded_tree = make_hier_tree(global_config, folded.nodes.reduce((a, c) => { a[c.id] = c; return a; }, {}));
    const old_pg_count = prev_pgs.length;
    const optimize_cfg = {
-        osd_weights: folded.nodes.reduce((a, c) => { if (Number(c.id)) { a[c.id] = c.size; } return a; }, {}),
+        osd_weights: folded.nodes.reduce((a, c) => { if (/^\d+$/.exec(c.id) && c.size != null) { a[c.id] = c.size||0; } return a; }, {}),
        combinator: use_rules
            // new algorithm:
            ? new RuleCombinator(folded_tree, rules, pool_cfg.max_osd_combinations)
@@ -84,7 +84,7 @@ function scale_pg_history(prev_pg_history, prev_pgs, new_pgs)
        finish_pg_history(merged_history[1]);
        for (let i = 0; i < new_pg_count; i++)
        {
-            new_pg_history[i] = { ...merged_history[1] };
+            new_pg_history[i] = JSON.parse(JSON.stringify(merged_history[1]));
        }
    }
    // Mark history keys for removed PGs as removed
@@ -102,7 +102,7 @@ function scale_pg_count(prev_pgs, new_pg_count)
    {
        for (let i = prev_pgs.length; i < new_pg_count; i++)
        {
-            prev_pgs[i] = prev_pgs[i % prev_pgs.length];
+            prev_pgs[i] = [ ...prev_pgs[i % prev_pgs.length] ];
        }
    }
    else if (prev_pgs.length > new_pg_count)
@@ -37,6 +37,7 @@ function derive_osd_stats(st, prev, prev_diff)
        const n = c.count - BigInt(pr && pr.count||0);
        diff.recovery_stats[op] = { ...c, bps: n > 0 ? b*1000n/timediff : 0n, iops: n > 0 ? n*1000n/timediff : 0n };
    }
+    diff.inode_stats = {};
    for (const pool_id in st.inode_stats||{})
    {
        diff.inode_stats[pool_id] = {};
@@ -1,6 +1,6 @@
 {
  "name": "vitastor",
-  "version": "3.0.0",
+  "version": "3.0.15",
  "description": "Low-level native bindings to Vitastor client library",
  "main": "index.js",
  "keywords": [
@@ -366,15 +366,38 @@ sub map_volume
    my $prefix = defined $scfg->{vitastor_prefix} ? $scfg->{vitastor_prefix} : 'pve/';

    my ($vtype, $img_name, $vmid) = $class->parse_volname($volname);
-    my $name = $img_name;
+    my $name = $prefix.$img_name;
    $name .= '@'.$snapname if $snapname;

    my $mapped = run_cli($scfg, [ 'ls' ], binary => '/usr/bin/vitastor-nbd');
-    my ($kerneldev) = grep { $mapped->{$_}->{image} eq $prefix.$name } keys %$mapped;
-    return $kerneldev if $kerneldev && -b $kerneldev; # already mapped
+    my ($kerneldev) = grep {
+        $mapped->{$_} && $mapped->{$_}->{image} && $mapped->{$_}->{image} eq $name
+    } keys %$mapped;

-    $kerneldev = run_cli($scfg, [ 'map', '--image', $prefix.$name ], binary => '/usr/bin/vitastor-nbd', json => 0);
-    return $kerneldev;
+    if ($kerneldev && -b $kerneldev)
+    {
+        my $size = `/usr/sbin/blockdev --getsize64 $kerneldev`;
+        return $kerneldev if $size && $size > 0;
+    }
+
+    my $map_out = run_cli($scfg, [ 'map', '--image', $name ], binary => '/usr/bin/vitastor-nbd', json => 0);
+    $map_out =~ s/^\s+|\s+$//gso;
+
+    # Wait until the device is started
+    for (my $i = 0; $i < 100; $i++)
+    {
+        $mapped = run_cli($scfg, [ 'ls' ], binary => '/usr/bin/vitastor-nbd');
+        ($kerneldev) = grep { $mapped->{$_} && $mapped->{$_}->{image} && $mapped->{$_}->{image} eq $name } keys %$mapped;
+        if ($kerneldev && -b $kerneldev)
+        {
+            my $size = `/usr/sbin/blockdev --getsize64 $kerneldev`;
+            return $kerneldev if $size && $size > 0;
+        }
+        select(undef, undef, undef, 0.1);
+    }
+
+    die "Failed to map Vitastor image $name via NBD".
+        ($map_out ? ", vitastor-nbd map returned '$map_out'" : "")."\n";
 }

 sub unmap_volume
@@ -383,13 +406,19 @@ sub unmap_volume
    my $prefix = defined $scfg->{vitastor_prefix} ? $scfg->{vitastor_prefix} : 'pve/';

    my ($vtype, $name, $vmid) = $class->parse_volname($volname);
+    $name = $prefix.$name;
    $name .= '@'.$snapname if $snapname;
-
    my $mapped = run_cli($scfg, [ 'ls' ], binary => '/usr/bin/vitastor-nbd');
-    my ($kerneldev) = grep { $mapped->{$_}->{image} eq $prefix.$name } keys %$mapped;
-    if ($kerneldev && -b $kerneldev)
+
+    my @kerneldevs = grep {
+        $mapped->{$_} && $mapped->{$_}->{image} && $mapped->{$_}->{image} eq $name
+    } keys %$mapped;
+
+    for my $kerneldev (@kerneldevs)
    {
-        run_cli($scfg, [ 'unmap', $kerneldev ], binary => '/usr/bin/vitastor-nbd', json => 0);
+        next if !$kerneldev || !-b $kerneldev;
+        eval { run_cli($scfg, [ 'unmap', $kerneldev ], binary => '/usr/bin/vitastor-nbd', json => 0); };
+        warn "Failed to unmap Vitastor image $name from $kerneldev: $@" if $@;
    }

    return 1;
@@ -405,7 +434,13 @@ sub activate_volume
 sub deactivate_volume
 {
    my ($class, $storeid, $scfg, $volname, $snapname, $cache) = @_;
-    $class->unmap_volume($storeid, $scfg, $volname, $snapname) if $scfg->{vitastor_nbd};
+
+    # Even with vitastor_nbd=0, Proxmox may call map_volume() for special
+    # volumes like tpmstate0 because swtpm needs a local file/block path.
+    # Therefore, always try to unmap an existing NBD mapping here.
+    # unmap_volume() is a no-op if the volume is not currently mapped.
+    $class->unmap_volume($storeid, $scfg, $volname, $snapname);
+
    return 1;
 }

@@ -50,7 +50,7 @@ from cinder.volume import configuration
 from cinder.volume import driver
 from cinder.volume import volume_utils

-VITASTOR_VERSION = '3.0.0'
+VITASTOR_VERSION = '3.0.15'

 LOG = logging.getLogger(__name__)

@@ -275,7 +275,7 @@ class VitastorDriver(driver.CloneableImageVD,
            LOG.exception('error getting vitastor pool stats: '+str(e))

        self._stats = stats
-        
+
    def get_volume_stats(self, refresh=False):
        """Get volume stats.
        If 'refresh' is True, run update the stats first.
@@ -291,6 +291,14 @@ class VitastorDriver(driver.CloneableImageVD,
        else:
            return (1 + resp['kvs'][0]['value'], resp['kvs'][0]['mod_revision'])

+    def _cli(self, descr, *args):
+        args = [ 'vitastor-cli', *args, *(self._vitastor_args()) ]
+        try:
+            self._execute(*args)
+        except processutils.ProcessExecutionError as exc:
+            LOG.error("Failed to "+descr+": "+exc)
+            raise exception.VolumeBackendAPIException(data = exc.stderr)
+
    def create_volume(self, volume):
        """Creates a logical volume."""

@@ -302,7 +310,7 @@ class VitastorDriver(driver.CloneableImageVD,

        LOG.debug("creating volume '%s'", vol_name)

-        self._create_image(vol_name, { 'size': size })
+        self._cli('create volume', 'create', vol_name, '--size', size)

        if volume.encryption_key_id:
            self._create_encrypted_volume(volume, volume.obj_context)
@@ -346,7 +354,7 @@ class VitastorDriver(driver.CloneableImageVD,
        snap_name = utils.convert_str(snapshot.name)
        if snap_name.find('@') >= 0 or snap_name.find('/') >= 0:
            raise exception.VolumeBackendAPIException(data = '@ and / are forbidden in volume and snapshot names')
-        self._create_snapshot(vol_name, vol_name+'@'+snap_name)
+        self._cli('create snapshot', 'snap-create', vol_name+'@'+snap_name)

    def snapshot_revert_use_temp_snapshot(self):
        """Disable the use of a temporary snapshot on revert."""
@@ -359,21 +367,8 @@ class VitastorDriver(driver.CloneableImageVD,
        snap_name = utils.convert_str(snapshot.name)

        # Delete the image and recreate it from the snapshot
-        args = [ 'vitastor-cli', 'rm', vol_name, *(self._vitastor_args()) ]
-        try:
-            self._execute(*args)
-        except processutils.ProcessExecutionError as exc:
-            LOG.error("Failed to delete image "+vol_name+": "+exc)
-            raise exception.VolumeBackendAPIException(data = exc.stderr)
-        args = [
-            'vitastor-cli', 'create', '--parent', vol_name+'@'+snap_name,
-            vol_name, *(self._vitastor_args())
-        ]
-        try:
-            self._execute(*args)
-        except processutils.ProcessExecutionError as exc:
-            LOG.error("Failed to recreate image "+vol_name+" from "+vol_name+"@"+snap_name+": "+exc)
-            raise exception.VolumeBackendAPIException(data = exc.stderr)
+        self._cli('delete image', 'rm', vol_name)
+        self._cli('recreate image', 'create', '--parent', vol_name+'@'+snap_name, vol_name)

    def delete_snapshot(self, snapshot):
        """Deletes a snapshot."""
@@ -381,15 +376,7 @@ class VitastorDriver(driver.CloneableImageVD,
        vol_name = utils.convert_str(snapshot.volume_name)
        snap_name = utils.convert_str(snapshot.name)

-        args = [
-            'vitastor-cli', 'rm', vol_name+'@'+snap_name,
-            *(self._vitastor_args())
-        ]
-        try:
-            self._execute(*args)
-        except processutils.ProcessExecutionError as exc:
-            LOG.error("Failed to remove snapshot "+vol_name+'@'+snap_name+": "+exc)
-            raise exception.VolumeBackendAPIException(data = exc.stderr)
+        self._cli('remove snapshot', 'rm', vol_name+'@'+snap_name)

    def _child_count(self, parents):
        children = 0
@@ -427,13 +414,7 @@ class VitastorDriver(driver.CloneableImageVD,
        if src_vref.admin_metadata.get('readonly') == 'True':
            # source volume is a volume-image cache entry or other readonly volume
            # clone without intermediate snapshot
-            src = self._get_image(src_name)
-            LOG.debug("creating image '%s' from '%s'", dest_name, src_name)
-            new_cfg = self._create_image(dest_name, {
-                'size': size,
-                'parent_id': src['idx']['id'],
-                'parent_pool_id': src['idx']['pool_id'],
-            })
+            self._cli('create clone', 'create', '--parent', src_name, '--size', size, dest_name)
            return {}

        clone_snap = "%s@%s.clone_snap" % (src_name, dest_name)
@@ -446,15 +427,12 @@ class VitastorDriver(driver.CloneableImageVD,
            clone_snap = dest_name
            make_img = False

-        LOG.debug("creating layer '%s' under '%s'", clone_snap, src_name)
-        new_cfg = self._create_snapshot(src_name, clone_snap, True)
+        LOG.debug("creating snapshot '%s'", clone_snap)
+        self._cli('create base snapshot', 'snap-create', '--allow-existing', '1', clone_snap)
+
        if make_img:
            # Then create a clone from it
-            new_cfg = self._create_image(dest_name, {
-                'size': size,
-                'parent_id': new_cfg['parent_id'],
-                'parent_pool_id': new_cfg['parent_pool_id'],
-            })
+            self._cli('create clone', 'create', '--parent', clone_snap, '--size', size, dest_name)

        return {}

@@ -464,7 +442,8 @@ class VitastorDriver(driver.CloneableImageVD,
        vol_name = utils.convert_str(volume.name)
        snap_name = utils.convert_str(snapshot.name)

-        snap = self._get_image('volume-'+snapshot.volume_id+'@'+snap_name)
+        src_snap = 'volume-'+snapshot.volume_id+'@'+snap_name
+        snap = self._get_image(src_snap)
        if not snap:
            raise exception.SnapshotNotFound(snapshot_id = snap_name)
        snap_inode_id = int(resp['responses'][0]['kvs'][0]['value']['id'])
@@ -473,12 +452,8 @@ class VitastorDriver(driver.CloneableImageVD,
        size = snap['cfg']['size']
        if int(volume.size):
            size = int(volume.size) * units.Gi
-        new_cfg = self._create_image(vol_name, {
-            'size': size,
-            'parent_id': snap['idx']['id'],
-            'parent_pool_id': snap['idx']['pool_id'],
-        })

+        self._cli('create clone', 'create', vol_name, '--size', size, '--parent', src_snap)
        return {}

    def _vitastor_args(self):
@@ -505,49 +480,7 @@ class VitastorDriver(driver.CloneableImageVD,
        """Deletes a logical volume."""

        vol_name = utils.convert_str(volume.name)
-
-        # Find the volume and all its snapshots
-        range_end = b'index/image/' + vol_name.encode('utf-8')
-        range_end = range_end[0 : len(range_end)-1] + six.int2byte(range_end[len(range_end)-1] + 1)
-        resp = self._etcd_txn({ 'success': [
-            { 'request_range': { 'key': 'index/image/'+vol_name, 'range_end': range_end } },
-        ] })
-        if len(resp['responses'][0]['kvs']) == 0:
-            # already deleted
-            LOG.info("volume %s no longer exists in backend", vol_name)
-            return
-        layers = resp['responses'][0]['kvs']
-        layer_ids = {}
-        for kv in layers:
-            inode_id = int(kv['value']['id'])
-            pool_id = int(kv['value']['pool_id'])
-            inode_pool_id = (pool_id << 48) | (inode_id & 0xffffffffffff)
-            layer_ids[inode_pool_id] = True
-
-        # Check if the volume has clones and raise 'busy' if so
-        children = self._child_count(layer_ids)
-        if children > 0:
-            raise exception.VolumeIsBusy(volume_name = vol_name)
-
-        # Clear data
-        for kv in layers:
-            args = [
-                'vitastor-cli', 'rm-data', '--pool', str(kv['value']['pool_id']),
-                '--inode', str(kv['value']['id']), '--progress', '0',
-                *(self._vitastor_args())
-            ]
-            try:
-                self._execute(*args)
-            except processutils.ProcessExecutionError as exc:
-                LOG.error("Failed to remove layer "+kv['key']+": "+exc)
-                raise exception.VolumeBackendAPIException(data = exc.stderr)
-
-        # Delete all layers from etcd
-        requests = []
-        for kv in layers:
-            requests.append({ 'request_delete_range': { 'key': kv['key'] } })
-            requests.append({ 'request_delete_range': { 'key': 'config/inode/'+str(kv['value']['pool_id'])+'/'+str(kv['value']['id']) } })
-        self._etcd_txn({ 'success': requests })
+        self._cli('delete volume', 'rm', '--matching', vol_name, vol_name+'@*', '--progress', '0')

    def retype(self, context, volume, new_type, diff, host):
        """Change extra type specifications for a volume."""
@@ -567,98 +500,6 @@ class VitastorDriver(driver.CloneableImageVD,
        """Removes an export for a logical volume."""
        pass

-    def _create_image(self, vol_name, cfg):
-        pool_s = str(self.cfg['pool_id'])
-        image_id = 0
-        while image_id == 0:
-            # check if the image already exists and find a free ID
-            resp = self._etcd_txn({ 'success': [
-                { 'request_range': { 'key': 'index/image/'+vol_name } },
-                { 'request_range': { 'key': 'index/maxid/'+pool_s } },
-            ] })
-            if len(resp['responses'][0]['kvs']) > 0:
-                # already exists
-                raise exception.VolumeBackendAPIException(data = 'Volume '+vol_name+' already exists')
-            image_id, id_mod = self._next_id(resp['responses'][1])
-            # try to create the image
-            resp = self._etcd_txn({ 'compare': [
-                { 'target': 'MOD', 'mod_revision': id_mod, 'key': 'index/maxid/'+pool_s },
-                { 'target': 'VERSION', 'version': 0, 'key': 'index/image/'+vol_name },
-                { 'target': 'VERSION', 'version': 0, 'key': 'config/inode/'+pool_s+'/'+str(image_id) },
-            ], 'success': [
-                { 'request_put': { 'key': 'index/maxid/'+pool_s, 'value': image_id } },
-                { 'request_put': { 'key': 'index/image/'+vol_name, 'value': json.dumps({
-                    'id': image_id, 'pool_id': self.cfg['pool_id']
-                }) } },
-                { 'request_put': { 'key': 'config/inode/'+pool_s+'/'+str(image_id), 'value': json.dumps({
-                    **cfg, 'name': vol_name,
-                }) } },
-            ] })
-            if not resp.get('succeeded'):
-                # repeat
-                image_id = 0
-
-    def _create_snapshot(self, vol_name, snap_vol_name, allow_existing = False):
-        while True:
-            # check if the image already exists and snapshot doesn't
-            resp = self._etcd_txn({ 'success': [
-                { 'request_range': { 'key': 'index/image/'+vol_name } },
-                { 'request_range': { 'key': 'index/image/'+snap_vol_name } },
-            ] })
-            if len(resp['responses'][0]['kvs']) == 0:
-                raise exception.VolumeBackendAPIException(data = 'Volume '+vol_name+' does not exist')
-            if len(resp['responses'][1]['kvs']) > 0:
-                if allow_existing:
-                    snap_idx = resp['responses'][1]['kvs'][0]['value']
-                    resp = self._etcd_txn({ 'success': [
-                        { 'request_range': { 'key': 'config/inode/'+str(snap_idx['pool_id'])+'/'+str(snap_idx['id']) } },
-                    ] })
-                    if len(resp['responses'][0]['kvs']) == 0:
-                        raise exception.VolumeBackendAPIException(data =
-                            'Volume '+snap_vol_name+' is already indexed, but does not exist'
-                        )
-                    return resp['responses'][0]['kvs'][0]['value']
-                raise exception.VolumeBackendAPIException(
-                    data = 'Volume '+snap_vol_name+' already exists'
-                )
-            vol_idx = resp['responses'][0]['kvs'][0]['value']
-            vol_idx_mod = resp['responses'][0]['kvs'][0]['mod_revision']
-            # get image inode config and find a new ID
-            resp = self._etcd_txn({ 'success': [
-                { 'request_range': { 'key': 'config/inode/'+str(vol_idx['pool_id'])+'/'+str(vol_idx['id']) } },
-                { 'request_range': { 'key': 'index/maxid/'+str(self.cfg['pool_id']) } },
-            ] })
-            if len(resp['responses'][0]['kvs']) == 0:
-                raise exception.VolumeBackendAPIException(data = 'Volume '+vol_name+' does not exist')
-            vol_cfg = resp['responses'][0]['kvs'][0]['value']
-            vol_mod = resp['responses'][0]['kvs'][0]['mod_revision']
-            new_id, id_mod = self._next_id(resp['responses'][1])
-            # try to redirect image to the new inode
-            new_cfg = {
-                **vol_cfg, 'name': vol_name, 'parent_id': vol_idx['id'], 'parent_pool_id': vol_idx['pool_id']
-            }
-            resp = self._etcd_txn({ 'compare': [
-                { 'target': 'MOD', 'mod_revision': vol_idx_mod, 'key': 'index/image/'+vol_name },
-                { 'target': 'MOD', 'mod_revision': vol_mod, 'key': 'config/inode/'+str(vol_idx['pool_id'])+'/'+str(vol_idx['id']) },
-                { 'target': 'MOD', 'mod_revision': id_mod, 'key': 'index/maxid/'+str(self.cfg['pool_id']) },
-                { 'target': 'VERSION', 'version': 0, 'key': 'index/image/'+snap_vol_name },
-                { 'target': 'VERSION', 'version': 0, 'key': 'config/inode/'+str(self.cfg['pool_id'])+'/'+str(new_id) },
-            ], 'success': [
-                { 'request_put': { 'key': 'index/maxid/'+str(self.cfg['pool_id']), 'value': new_id } },
-                { 'request_put': { 'key': 'index/image/'+vol_name, 'value': json.dumps({
-                    'id': new_id, 'pool_id': self.cfg['pool_id']
-                }) } },
-                { 'request_put': { 'key': 'config/inode/'+str(self.cfg['pool_id'])+'/'+str(new_id), 'value': json.dumps(new_cfg) } },
-                { 'request_put': { 'key': 'index/image/'+snap_vol_name, 'value': json.dumps({
-                    'id': vol_idx['id'], 'pool_id': vol_idx['pool_id']
-                }) } },
-                { 'request_put': { 'key': 'config/inode/'+str(vol_idx['pool_id'])+'/'+str(vol_idx['id']), 'value': json.dumps({
-                    **vol_cfg, 'name': snap_vol_name, 'readonly': True
-                }) } }
-            ] })
-            if resp.get('succeeded'):
-                return new_cfg
-
    def initialize_connection(self, volume, connector):
        data = {
            'driver_volume_type': 'vitastor',
@@ -697,13 +538,9 @@ class VitastorDriver(driver.CloneableImageVD,
                    size = int(volume.size) * units.Gi
                    dest_name = utils.convert_str(volume.name)
                    # Find or create the base snapshot
-                    snap_cfg = self._create_snapshot(base_vol.name, base_vol.name+'@.clone_snap', True)
+                    self._cli('create base snapshot', 'create', '--allow-existing', '1', base_vol.name+'@.clone_snap')
                    # Then create a clone from it
-                    new_cfg = self._create_image(dest_name, {
-                        'size': size,
-                        'parent_id': snap_cfg['parent_id'],
-                        'parent_pool_id': snap_cfg['parent_pool_id'],
-                    })
+                    self._cli('create clone', 'create', dest_name, '--size', size, '--parent', base_vol.name+'@.clone_snap')
                    return ({}, True)
        return ({}, False)

@@ -770,26 +607,8 @@ class VitastorDriver(driver.CloneableImageVD,
    def extend_volume(self, volume, new_size):
        """Extend an existing volume."""
        vol_name = utils.convert_str(volume.name)
-        while True:
-            vol = self._get_image(vol_name)
-            if not vol:
-                raise exception.VolumeBackendAPIException(data = 'Volume '+vol_name+' does not exist')
-            # change size
-            size = int(new_size) * units.Gi
-            if size == vol['cfg']['size']:
-                break
-            resp = self._etcd_txn({ 'compare': [ {
-                'target': 'MOD',
-                'mod_revision': vol['cfg_mod'],
-                'key': 'config/inode/'+str(vol['idx']['pool_id'])+'/'+str(vol['idx']['id']),
-            } ], 'success': [
-                { 'request_put': {
-                    'key': 'config/inode/'+str(vol['idx']['pool_id'])+'/'+str(vol['idx']['id']),
-                    'value': json.dumps({ **vol['cfg'], 'size': size }),
-                } },
-            ] })
-            if resp.get('succeeded'):
-                break
+        size = int(new_size) * units.Gi
+        self._cli('extend volume', 'modify', vol_name, '--resize', new_size)
        LOG.debug(
            "Extend volume from %(old_size)s GB to %(new_size)s GB.",
            {'old_size': volume.size, 'new_size': new_size}
@@ -862,28 +681,7 @@ class VitastorDriver(driver.CloneableImageVD,
        """
        from_name = self._get_existing_name(existing_ref)
        to_name = utils.convert_str(volume.name)
-        self._rename(from_name, to_name)
-
-    def _rename(self, from_name, to_name):
-        while True:
-            vol = self._get_image(from_name)
-            if not vol:
-                raise exception.VolumeBackendAPIException(data = 'Volume '+from_name+' does not exist')
-            to = self._get_image(to_name)
-            if to:
-                raise exception.VolumeBackendAPIException(data = 'Volume '+to_name+' already exists')
-            resp = self._etcd_txn({ 'compare': [
-                { 'target': 'MOD', 'mod_revision': vol['idx_mod'], 'key': 'index/image/'+vol['cfg']['name'] },
-                { 'target': 'MOD', 'mod_revision': vol['cfg_mod'], 'key': 'config/inode/'+str(vol['idx']['pool_id'])+'/'+str(vol['idx']['id']) },
-                { 'target': 'VERSION', 'version': 0, 'key': 'index/image/'+to_name },
-            ], 'success': [
-                { 'request_delete_range': { 'key': 'index/image/'+vol['cfg']['name'] } },
-                { 'request_put': { 'key': 'index/image/'+to_name, 'value': json.dumps(vol['idx']) } },
-                { 'request_put': { 'key': 'config/inode/'+str(vol['idx']['pool_id'])+'/'+str(vol['idx']['id']),
-                    'value': json.dumps({ **vol['cfg'], 'name': to_name }) } },
-            ] })
-            if resp.get('succeeded'):
-                break
+        self._cli('rename', 'modify', from_name, '--rename', to_name)

    def unmanage(self, volume):
        pass
@@ -956,7 +754,7 @@ class VitastorDriver(driver.CloneableImageVD,
        snap_name = self._get_existing_name(existing_ref)
        from_name = vol_name+'@'+snap_name
        to_name = vol_name+'@'+utils.convert_str(snapshot.name)
-        self._rename(from_name, to_name)
+        self._cli('rename', 'modify', from_name, '--rename', to_name)

    def unmanage_snapshot(self, snapshot):
        """Removes the specified snapshot from Cinder management."""
@@ -0,0 +1,637 @@
+diff --git a/include/libvirt/libvirt-storage.h b/include/libvirt/libvirt-storage.h
+index aaad4a3da1..5f5daa8341 100644
+--- a/include/libvirt/libvirt-storage.h
+++ b/include/libvirt/libvirt-storage.h
+@@ -326,6 +326,7 @@ typedef enum {
+     VIR_CONNECT_LIST_STORAGE_POOLS_ZFS           = 1 << 17, /* (Since: 1.2.8) */
+     VIR_CONNECT_LIST_STORAGE_POOLS_VSTORAGE      = 1 << 18, /* (Since: 3.1.0) */
+     VIR_CONNECT_LIST_STORAGE_POOLS_ISCSI_DIRECT  = 1 << 19, /* (Since: 5.6.0) */
+    VIR_CONNECT_LIST_STORAGE_POOLS_VITASTOR      = 1 << 20, /* (Since: 5.0.0) */
+ } virConnectListAllStoragePoolsFlags;
+ 
+ int                     virConnectListAllStoragePools(virConnectPtr conn,
+diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
+index 9ca5c2450c..cc52f00c0c 100644
+--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
+@@ -7453,7 +7453,8 @@ virDomainDiskSourceNetworkParse(xmlNodePtr node,
+     src->configFile = virXPathString("string(./config/@file)", ctxt);
+ 
+     if (src->protocol == VIR_STORAGE_NET_PROTOCOL_HTTP ||
+-        src->protocol == VIR_STORAGE_NET_PROTOCOL_HTTPS)
+        src->protocol == VIR_STORAGE_NET_PROTOCOL_HTTPS ||
+        src->protocol == VIR_STORAGE_NET_PROTOCOL_VITASTOR)
+         src->query = virXMLPropString(node, "query");
+ 
+     if (virDomainStorageNetworkParseHosts(node, ctxt, &src->hosts, &src->nhosts) < 0)
+@@ -32187,6 +32188,7 @@ virDomainStorageSourceTranslateSourcePool(virStorageSource *src,
+ 
+     case VIR_STORAGE_POOL_MPATH:
+     case VIR_STORAGE_POOL_RBD:
+    case VIR_STORAGE_POOL_VITASTOR:
+     case VIR_STORAGE_POOL_SHEEPDOG:
+     case VIR_STORAGE_POOL_GLUSTER:
+     case VIR_STORAGE_POOL_LAST:
+diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
+index 7346a61731..83e94d762e 100644
+--- a/src/conf/domain_validate.c
+++ b/src/conf/domain_validate.c
+@@ -520,6 +520,7 @@ virDomainDiskDefValidateSourceChainOne(const virStorageSource *src)
+         case VIR_STORAGE_NET_PROTOCOL_RBD:
+             break;
+ 
+        case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+         case VIR_STORAGE_NET_PROTOCOL_NBD:
+         case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
+         case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
+@@ -592,7 +593,7 @@ virDomainDiskDefValidateSourceChainOne(const virStorageSource *src)
+         }
+     }
+ 
+-    /* internal snapshots and config files are currently supported only with rbd: */
+    /* internal snapshots are currently supported only with rbd: */
+     if (virStorageSourceGetActualType(src) != VIR_STORAGE_TYPE_NETWORK &&
+         src->protocol != VIR_STORAGE_NET_PROTOCOL_RBD) {
+         if (src->snapshot) {
+@@ -600,10 +601,14 @@ virDomainDiskDefValidateSourceChainOne(const virStorageSource *src)
+                            _("<snapshot> element is currently supported only with 'rbd' disks"));
+             return -1;
+         }
+-
+    }
+    /* config files are currently supported only with rbd and vitastor: */
+    if (virStorageSourceGetActualType(src) != VIR_STORAGE_TYPE_NETWORK &&
+        src->protocol != VIR_STORAGE_NET_PROTOCOL_RBD &&
+        src->protocol != VIR_STORAGE_NET_PROTOCOL_VITASTOR) {
+         if (src->configFile) {
+             virReportError(VIR_ERR_XML_ERROR, "%s",
+-                           _("<config> element is currently supported only with 'rbd' disks"));
+                           _("<config> element is currently supported only with 'rbd' and 'vitastor' disks"));
+             return -1;
+         }
+     }
+diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng
+index 114dd3f96f..c71f9a3277 100644
+--- a/src/conf/schemas/domaincommon.rng
+++ b/src/conf/schemas/domaincommon.rng
+@@ -2093,6 +2093,35 @@
+     </element>
+   </define>
+ 
+  <define name="diskSourceNetworkProtocolVitastor">
+    <element name="source">
+      <interleave>
+        <attribute name="protocol">
+          <value>vitastor</value>
+        </attribute>
+        <ref name="diskSourceCommon"/>
+        <optional>
+          <attribute name="name"/>
+        </optional>
+        <optional>
+          <attribute name="query"/>
+        </optional>
+        <zeroOrMore>
+          <ref name="diskSourceNetworkHost"/>
+        </zeroOrMore>
+        <optional>
+          <element name="config">
+            <attribute name="file">
+              <ref name="absFilePath"/>
+            </attribute>
+            <empty/>
+          </element>
+        </optional>
+        <empty/>
+      </interleave>
+    </element>
+  </define>
+
+   <define name="diskSourceNetworkProtocolISCSI">
+     <element name="source">
+       <attribute name="protocol">
+@@ -2443,6 +2472,7 @@
+       <ref name="diskSourceNetworkProtocolSimple"/>
+       <ref name="diskSourceNetworkProtocolVxHS"/>
+       <ref name="diskSourceNetworkProtocolNFS"/>
+      <ref name="diskSourceNetworkProtocolVitastor"/>
+     </choice>
+   </define>
+ 
+diff --git a/src/conf/storage_conf.c b/src/conf/storage_conf.c
+index 1dc9365bf2..a8a736be81 100644
+--- a/src/conf/storage_conf.c
+++ b/src/conf/storage_conf.c
+@@ -56,7 +56,7 @@ VIR_ENUM_IMPL(virStoragePool,
+               "logical", "disk", "iscsi",
+               "iscsi-direct", "scsi", "mpath",
+               "rbd", "sheepdog", "gluster",
+-              "zfs", "vstorage",
+              "zfs", "vstorage", "vitastor",
+ );
+ 
+ VIR_ENUM_IMPL(virStoragePoolFormatFileSystem,
+@@ -242,6 +242,18 @@ static virStoragePoolTypeInfo poolTypeInfo[] = {
+           .formatToString = virStorageFileFormatTypeToString,
+       }
+     },
+    {.poolType = VIR_STORAGE_POOL_VITASTOR,
+     .poolOptions = {
+         .flags = (VIR_STORAGE_POOL_SOURCE_HOST |
+                   VIR_STORAGE_POOL_SOURCE_NETWORK |
+                   VIR_STORAGE_POOL_SOURCE_NAME),
+      },
+      .volOptions = {
+          .defaultFormat = VIR_STORAGE_FILE_RAW,
+          .formatFromString = virStorageVolumeFormatFromString,
+          .formatToString = virStorageFileFormatTypeToString,
+      }
+    },
+     {.poolType = VIR_STORAGE_POOL_SHEEPDOG,
+      .poolOptions = {
+          .flags = (VIR_STORAGE_POOL_SOURCE_HOST |
+@@ -538,6 +550,11 @@ virStoragePoolDefParseSource(xmlXPathContextPtr ctxt,
+                        _("element 'name' is mandatory for RBD pool"));
+         return -1;
+     }
+    if (pool_type == VIR_STORAGE_POOL_VITASTOR && source->name == NULL) {
+        virReportError(VIR_ERR_XML_ERROR, "%s",
+                       _("element 'name' is mandatory for Vitastor pool"));
+        return -1;
+    }
+ 
+     if (options->formatFromString) {
+         g_autofree char *format = NULL;
+@@ -1127,6 +1144,7 @@ virStoragePoolDefFormatBuf(virBuffer *buf,
+     /* RBD, Sheepdog, Gluster and Iscsi-direct devices are not local block devs nor
+      * files, so they don't have a target */
+     if (def->type != VIR_STORAGE_POOL_RBD &&
+        def->type != VIR_STORAGE_POOL_VITASTOR &&
+         def->type != VIR_STORAGE_POOL_SHEEPDOG &&
+         def->type != VIR_STORAGE_POOL_GLUSTER &&
+         def->type != VIR_STORAGE_POOL_ISCSI_DIRECT) {
+diff --git a/src/conf/storage_conf.h b/src/conf/storage_conf.h
+index fc67957cfe..720c07ef74 100644
+--- a/src/conf/storage_conf.h
+++ b/src/conf/storage_conf.h
+@@ -103,6 +103,7 @@ typedef enum {
+     VIR_STORAGE_POOL_GLUSTER,  /* Gluster device */
+     VIR_STORAGE_POOL_ZFS,      /* ZFS */
+     VIR_STORAGE_POOL_VSTORAGE, /* Virtuozzo Storage */
+    VIR_STORAGE_POOL_VITASTOR, /* Vitastor */
+ 
+     VIR_STORAGE_POOL_LAST,
+ } virStoragePoolType;
+@@ -454,6 +455,7 @@ VIR_ENUM_DECL(virStoragePartedFs);
+                  VIR_CONNECT_LIST_STORAGE_POOLS_SCSI     | \
+                  VIR_CONNECT_LIST_STORAGE_POOLS_MPATH    | \
+                  VIR_CONNECT_LIST_STORAGE_POOLS_RBD      | \
+                 VIR_CONNECT_LIST_STORAGE_POOLS_VITASTOR | \
+                  VIR_CONNECT_LIST_STORAGE_POOLS_SHEEPDOG | \
+                  VIR_CONNECT_LIST_STORAGE_POOLS_GLUSTER  | \
+                  VIR_CONNECT_LIST_STORAGE_POOLS_ZFS      | \
+diff --git a/src/conf/storage_source_conf.c b/src/conf/storage_source_conf.c
+index d7b9bdfecb..38aefd0dd4 100644
+--- a/src/conf/storage_source_conf.c
+++ b/src/conf/storage_source_conf.c
+@@ -90,6 +90,7 @@ VIR_ENUM_IMPL(virStorageNetProtocol,
+               "ssh",
+               "vxhs",
+               "nfs",
+              "vitastor",
+ );
+ 
+ 
+@@ -1317,6 +1318,7 @@ virStorageSourceNetworkDefaultPort(virStorageNetProtocol protocol)
+         case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
+             return 24007;
+ 
+        case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+         case VIR_STORAGE_NET_PROTOCOL_RBD:
+             /* we don't provide a default for RBD */
+             return 0;
+diff --git a/src/conf/storage_source_conf.h b/src/conf/storage_source_conf.h
+index 22c35d420d..f1e32ea83d 100644
+--- a/src/conf/storage_source_conf.h
+++ b/src/conf/storage_source_conf.h
+@@ -131,6 +131,7 @@ typedef enum {
+     VIR_STORAGE_NET_PROTOCOL_SSH,
+     VIR_STORAGE_NET_PROTOCOL_VXHS,
+     VIR_STORAGE_NET_PROTOCOL_NFS,
+    VIR_STORAGE_NET_PROTOCOL_VITASTOR,
+ 
+     VIR_STORAGE_NET_PROTOCOL_LAST
+ } virStorageNetProtocol;
+diff --git a/src/conf/virstorageobj.c b/src/conf/virstorageobj.c
+index 59fa5da372..4739167f5f 100644
+--- a/src/conf/virstorageobj.c
+++ b/src/conf/virstorageobj.c
+@@ -1438,6 +1438,7 @@ virStoragePoolObjSourceFindDuplicateCb(const void *payload,
+             return 1;
+         break;
+ 
+    case VIR_STORAGE_POOL_VITASTOR:
+     case VIR_STORAGE_POOL_ISCSI_DIRECT:
+     case VIR_STORAGE_POOL_RBD:
+     case VIR_STORAGE_POOL_LAST:
+@@ -1921,6 +1922,8 @@ virStoragePoolObjMatch(virStoragePoolObj *obj,
+                (obj->def->type == VIR_STORAGE_POOL_MPATH))   ||
+               (MATCH(VIR_CONNECT_LIST_STORAGE_POOLS_RBD) &&
+                (obj->def->type == VIR_STORAGE_POOL_RBD))     ||
+              (MATCH(VIR_CONNECT_LIST_STORAGE_POOLS_VITASTOR) &&
+               (obj->def->type == VIR_STORAGE_POOL_VITASTOR)) ||
+               (MATCH(VIR_CONNECT_LIST_STORAGE_POOLS_SHEEPDOG) &&
+                (obj->def->type == VIR_STORAGE_POOL_SHEEPDOG)) ||
+               (MATCH(VIR_CONNECT_LIST_STORAGE_POOLS_GLUSTER) &&
+diff --git a/src/libvirt-storage.c b/src/libvirt-storage.c
+index db7660aac4..561df34709 100644
+--- a/src/libvirt-storage.c
+++ b/src/libvirt-storage.c
+@@ -94,6 +94,7 @@ virStoragePoolGetConnect(virStoragePoolPtr pool)
+  * VIR_CONNECT_LIST_STORAGE_POOLS_SCSI
+  * VIR_CONNECT_LIST_STORAGE_POOLS_MPATH
+  * VIR_CONNECT_LIST_STORAGE_POOLS_RBD
+ * VIR_CONNECT_LIST_STORAGE_POOLS_VITASTOR
+  * VIR_CONNECT_LIST_STORAGE_POOLS_SHEEPDOG
+  * VIR_CONNECT_LIST_STORAGE_POOLS_GLUSTER
+  * VIR_CONNECT_LIST_STORAGE_POOLS_ZFS
+diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
+index 2b988157fa..9d0eb47b25 100644
+--- a/src/libxl/libxl_conf.c
+++ b/src/libxl/libxl_conf.c
+@@ -1069,6 +1069,7 @@ libxlMakeNetworkDiskSrcStr(virStorageSource *src,
+     case VIR_STORAGE_NET_PROTOCOL_SSH:
+     case VIR_STORAGE_NET_PROTOCOL_VXHS:
+     case VIR_STORAGE_NET_PROTOCOL_NFS:
+    case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+     case VIR_STORAGE_NET_PROTOCOL_LAST:
+     case VIR_STORAGE_NET_PROTOCOL_NONE:
+         virReportError(VIR_ERR_NO_SUPPORT,
+diff --git a/src/libxl/xen_xl.c b/src/libxl/xen_xl.c
+index e72e7d7f44..8482c21805 100644
+--- a/src/libxl/xen_xl.c
+++ b/src/libxl/xen_xl.c
+@@ -1461,6 +1461,7 @@ xenFormatXLDiskSrcNet(virStorageSource *src)
+     case VIR_STORAGE_NET_PROTOCOL_SSH:
+     case VIR_STORAGE_NET_PROTOCOL_VXHS:
+     case VIR_STORAGE_NET_PROTOCOL_NFS:
+    case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+     case VIR_STORAGE_NET_PROTOCOL_LAST:
+     case VIR_STORAGE_NET_PROTOCOL_NONE:
+         virReportError(VIR_ERR_NO_SUPPORT,
+diff --git a/src/qemu/qemu_block.c b/src/qemu/qemu_block.c
+index 9b43279797..459d8e8a65 100644
+--- a/src/qemu/qemu_block.c
+++ b/src/qemu/qemu_block.c
+@@ -743,6 +743,38 @@ qemuBlockStorageSourceGetRBDProps(virStorageSource *src,
+ }
+ 
+ 
+static virJSONValue *
+qemuBlockStorageSourceGetVitastorProps(virStorageSource *src)
+{
+    virJSONValue *ret = NULL;
+    virStorageNetHostDef *host;
+    size_t i;
+    g_auto(virBuffer) buf = VIR_BUFFER_INITIALIZER;
+    g_autofree char *etcd = NULL;
+
+    for (i = 0; i < src->nhosts; i++) {
+        host = src->hosts + i;
+        if ((virStorageNetHostTransport)host->transport != VIR_STORAGE_NET_HOST_TRANS_TCP) {
+            return NULL;
+        }
+        virBufferAsprintf(&buf, i > 0 ? ",%s:%u" : "%s:%u", host->name, host->port);
+    }
+    if (src->nhosts > 0) {
+        etcd = virBufferContentAndReset(&buf);
+    }
+
+    if (virJSONValueObjectAdd(&ret,
+                              "S:etcd-host", etcd,
+                              "S:etcd-prefix", src->query,
+                              "S:config-path", src->configFile,
+                              "s:image", src->path,
+                              NULL) < 0)
+        return NULL;
+
+    return ret;
+}
+
+
+ static virJSONValue *
+ qemuBlockStorageSourceGetSshProps(virStorageSource *src)
+ {
+@@ -1094,6 +1126,12 @@ qemuBlockStorageSourceGetBackendProps(virStorageSource *src,
+                 return NULL;
+             break;
+ 
+        case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+            driver = "vitastor";
+            if (!(fileprops = qemuBlockStorageSourceGetVitastorProps(src)))
+                return NULL;
+            break;
+
+         case VIR_STORAGE_NET_PROTOCOL_SSH:
+             driver = "ssh";
+             if (!(fileprops = qemuBlockStorageSourceGetSshProps(src)))
+@@ -1997,6 +2035,7 @@ qemuBlockGetBackingStoreString(virStorageSource *src,
+ 
+             case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
+             case VIR_STORAGE_NET_PROTOCOL_RBD:
+            case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+             case VIR_STORAGE_NET_PROTOCOL_VXHS:
+             case VIR_STORAGE_NET_PROTOCOL_NFS:
+             case VIR_STORAGE_NET_PROTOCOL_SSH:
+@@ -2377,6 +2416,12 @@ qemuBlockStorageSourceCreateGetStorageProps(virStorageSource *src,
+                 return -1;
+             break;
+ 
+        case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+            driver = "vitastor";
+            if (!(location = qemuBlockStorageSourceGetVitastorProps(src)))
+                return -1;
+            break;
+
+         case VIR_STORAGE_NET_PROTOCOL_SSH:
+             if (srcPriv->nbdkitProcess) {
+                 /* disk creation not yet supported with nbdkit, and even if it
+diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
+index ac56fc7cb4..9e407b4aab 100644
+--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
+@@ -4677,7 +4677,8 @@ qemuDomainValidateStorageSource(virStorageSource *src,
+     if (src->query &&
+         (actualType != VIR_STORAGE_TYPE_NETWORK ||
+          (src->protocol != VIR_STORAGE_NET_PROTOCOL_HTTPS &&
+-          src->protocol != VIR_STORAGE_NET_PROTOCOL_HTTP))) {
+          src->protocol != VIR_STORAGE_NET_PROTOCOL_HTTP &&
+          src->protocol != VIR_STORAGE_NET_PROTOCOL_VITASTOR))) {
+         virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                        _("query is supported only with HTTP(S) protocols"));
+         return -1;
+@@ -9103,6 +9104,7 @@ qemuDomainPrepareStorageSourceTLS(virStorageSource *src,
+         break;
+ 
+     case VIR_STORAGE_NET_PROTOCOL_RBD:
+    case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+     case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
+     case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
+     case VIR_STORAGE_NET_PROTOCOL_ISCSI:
+diff --git a/src/qemu/qemu_snapshot.c b/src/qemu/qemu_snapshot.c
+index e738afffc3..37d64f469b 100644
+--- a/src/qemu/qemu_snapshot.c
+++ b/src/qemu/qemu_snapshot.c
+@@ -665,6 +665,7 @@ qemuSnapshotPrepareDiskExternalInactive(virDomainSnapshotDiskDef *snapdisk,
+         case VIR_STORAGE_NET_PROTOCOL_NONE:
+         case VIR_STORAGE_NET_PROTOCOL_NBD:
+         case VIR_STORAGE_NET_PROTOCOL_RBD:
+        case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+         case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
+         case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
+         case VIR_STORAGE_NET_PROTOCOL_ISCSI:
+@@ -893,6 +894,7 @@ qemuSnapshotPrepareDiskInternal(virDomainDiskDef *disk,
+         case VIR_STORAGE_NET_PROTOCOL_NONE:
+         case VIR_STORAGE_NET_PROTOCOL_NBD:
+         case VIR_STORAGE_NET_PROTOCOL_RBD:
+        case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+         case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
+         case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
+         case VIR_STORAGE_NET_PROTOCOL_ISCSI:
+diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
+index e19e032427..59f91f4710 100644
+--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
+@@ -1626,6 +1626,7 @@ storageVolLookupByPathCallback(virStoragePoolObj *obj,
+ 
+         case VIR_STORAGE_POOL_GLUSTER:
+         case VIR_STORAGE_POOL_RBD:
+        case VIR_STORAGE_POOL_VITASTOR:
+         case VIR_STORAGE_POOL_SHEEPDOG:
+         case VIR_STORAGE_POOL_ZFS:
+         case VIR_STORAGE_POOL_LAST:
+diff --git a/src/storage_file/storage_source_backingstore.c b/src/storage_file/storage_source_backingstore.c
+index 821378883c..2211f6891b 100644
+--- a/src/storage_file/storage_source_backingstore.c
+++ b/src/storage_file/storage_source_backingstore.c
+@@ -264,6 +264,75 @@ virStorageSourceParseRBDColonString(const char *rbdstr,
+ }
+ 
+ 
+static int
+virStorageSourceParseVitastorColonString(const char *colonstr,
+                                         virStorageSource *src)
+{
+    char *p, *e, *next;
+    g_autofree char *options = NULL;
+
+    /* optionally skip the "vitastor:" prefix if provided */
+    if (STRPREFIX(colonstr, "vitastor:"))
+        colonstr += strlen("vitastor:");
+
+    options = g_strdup(colonstr);
+
+    p = options;
+    while (*p) {
+        /* find : delimiter or end of string */
+        for (e = p; *e && *e != ':'; ++e) {
+            if (*e == '\\') {
+                e++;
+                if (*e == '\0')
+                    break;
+            }
+        }
+        if (*e == '\0') {
+            next = e;    /* last kv pair */
+        } else {
+            next = e + 1;
+            *e = '\0';
+        }
+
+        if (STRPREFIX(p, "image=")) {
+            src->path = g_strdup(p + strlen("image="));
+        } else if (STRPREFIX(p, "etcd-prefix=")) {
+            src->query = g_strdup(p + strlen("etcd-prefix="));
+        } else if (STRPREFIX(p, "config-path=")) {
+            src->configFile = g_strdup(p + strlen("config-path="));
+        } else if (STRPREFIX(p, "etcd-host=")) {
+            char *h, *sep;
+
+            h = p + strlen("etcd-host=");
+            while (h < e) {
+                for (sep = h; sep < e; ++sep) {
+                    if (*sep == '\\' && (sep[1] == ',' ||
+                                         sep[1] == ';' ||
+                                         sep[1] == ' ')) {
+                        *sep = '\0';
+                        sep += 2;
+                        break;
+                    }
+                }
+
+                if (virStorageSourceRBDAddHost(src, h) < 0)
+                    return -1;
+
+                h = sep;
+            }
+        }
+
+        p = next;
+    }
+
+    if (!src->path) {
+        return -1;
+    }
+
+    return 0;
+}
+
+
+ static int
+ virStorageSourceParseNBDColonString(const char *nbdstr,
+                                     virStorageSource *src)
+@@ -379,6 +448,11 @@ virStorageSourceParseBackingColon(virStorageSource *src,
+             return -1;
+         break;
+ 
+    case VIR_STORAGE_NET_PROTOCOL_VITASTOR:
+        if (virStorageSourceParseVitastorColonString(path, src) < 0)
+            return -1;
+        break;
+
+     case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
+     case VIR_STORAGE_NET_PROTOCOL_LAST:
+     case VIR_STORAGE_NET_PROTOCOL_NONE:
+@@ -953,6 +1027,54 @@ virStorageSourceParseBackingJSONRBD(virStorageSource *src,
+     return 0;
+ }
+ 
+static int
+virStorageSourceParseBackingJSONVitastor(virStorageSource *src,
+                                         virJSONValue *json,
+                                         const char *jsonstr G_GNUC_UNUSED,
+                                         int opaque G_GNUC_UNUSED)
+{
+    const char *filename;
+    const char *image = virJSONValueObjectGetString(json, "image");
+    const char *conf = virJSONValueObjectGetString(json, "config-path");
+    const char *etcd_prefix = virJSONValueObjectGetString(json, "etcd-prefix");
+    virJSONValue *servers = virJSONValueObjectGetArray(json, "server");
+    size_t nservers;
+    size_t i;
+
+    src->type = VIR_STORAGE_TYPE_NETWORK;
+    src->protocol = VIR_STORAGE_NET_PROTOCOL_VITASTOR;
+
+    /* legacy syntax passed via 'filename' option */
+    if ((filename = virJSONValueObjectGetString(json, "filename")))
+        return virStorageSourceParseVitastorColonString(filename, src);
+
+    if (!image) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("missing image name in Vitastor backing volume "
+                         "JSON specification"));
+        return -1;
+    }
+
+    src->path = g_strdup(image);
+    src->configFile = g_strdup(conf);
+    src->query = g_strdup(etcd_prefix);
+
+    if (servers) {
+        nservers = virJSONValueArraySize(servers);
+
+        src->hosts = g_new0(virStorageNetHostDef, nservers);
+        src->nhosts = nservers;
+
+        for (i = 0; i < nservers; i++) {
+            if (virStorageSourceParseBackingJSONInetSocketAddress(src->hosts + i,
+                                                                  virJSONValueArrayGet(servers, i)) < 0)
+                return -1;
+        }
+    }
+
+    return 0;
+}
+
+ static int
+ virStorageSourceParseBackingJSONRaw(virStorageSource *src,
+                                     virJSONValue *json,
+@@ -1130,6 +1252,7 @@ static const struct virStorageSourceJSONDriverParser jsonParsers[] = {
+     {"sheepdog", false, virStorageSourceParseBackingJSONSheepdog, 0},
+     {"ssh", false, virStorageSourceParseBackingJSONSSH, 0},
+     {"rbd", false, virStorageSourceParseBackingJSONRBD, 0},
+    {"vitastor", false, virStorageSourceParseBackingJSONVitastor, 0},
+     {"raw", true, virStorageSourceParseBackingJSONRaw, 0},
+     {"nfs", false, virStorageSourceParseBackingJSONNFS, 0},
+     {"vxhs", false, virStorageSourceParseBackingJSONVxHS, 0},
+diff --git a/src/test/test_driver.c b/src/test/test_driver.c
+index 1165689de7..bba846351c 100644
+--- a/src/test/test_driver.c
+++ b/src/test/test_driver.c
+@@ -7345,6 +7345,7 @@ testStorageVolumeTypeForPool(int pooltype)
+     case VIR_STORAGE_POOL_ISCSI_DIRECT:
+     case VIR_STORAGE_POOL_GLUSTER:
+     case VIR_STORAGE_POOL_RBD:
+    case VIR_STORAGE_POOL_VITASTOR:
+         return VIR_STORAGE_VOL_NETWORK;
+     case VIR_STORAGE_POOL_LOGICAL:
+     case VIR_STORAGE_POOL_DISK:
+diff --git a/tests/storagepoolcapsschemadata/poolcaps-fs.xml b/tests/storagepoolcapsschemadata/poolcaps-fs.xml
+index eee75af746..8bd0a57bdd 100644
+--- a/tests/storagepoolcapsschemadata/poolcaps-fs.xml
+++ b/tests/storagepoolcapsschemadata/poolcaps-fs.xml
+@@ -204,4 +204,11 @@
+       </enum>
+     </volOptions>
+   </pool>
+  <pool type='vitastor' supported='no'>
+    <volOptions>
+      <defaultFormat type='raw'/>
+      <enum name='targetFormatType'>
+      </enum>
+    </volOptions>
+  </pool>
+ </storagepoolCapabilities>
+diff --git a/tests/storagepoolcapsschemadata/poolcaps-full.xml b/tests/storagepoolcapsschemadata/poolcaps-full.xml
+index 805950a937..852df0de16 100644
+--- a/tests/storagepoolcapsschemadata/poolcaps-full.xml
+++ b/tests/storagepoolcapsschemadata/poolcaps-full.xml
+@@ -204,4 +204,11 @@
+       </enum>
+     </volOptions>
+   </pool>
+  <pool type='vitastor' supported='yes'>
+    <volOptions>
+      <defaultFormat type='raw'/>
+      <enum name='targetFormatType'>
+      </enum>
+    </volOptions>
+  </pool>
+ </storagepoolCapabilities>
+diff --git a/tests/storagepoolxml2argvtest.c b/tests/storagepoolxml2argvtest.c
+index d5c2531ab8..b19308ac38 100644
+--- a/tests/storagepoolxml2argvtest.c
+++ b/tests/storagepoolxml2argvtest.c
+@@ -57,6 +57,7 @@ testCompareXMLToArgvFiles(bool shouldFail,
+     case VIR_STORAGE_POOL_GLUSTER:
+     case VIR_STORAGE_POOL_ZFS:
+     case VIR_STORAGE_POOL_VSTORAGE:
+    case VIR_STORAGE_POOL_VITASTOR:
+     case VIR_STORAGE_POOL_LAST:
+     default:
+         VIR_TEST_DEBUG("pool type '%s' has no xml2argv test", defTypeStr);
+diff --git a/tools/virsh-pool.c b/tools/virsh-pool.c
+index 2010ef1356..072e2ff9e8 100644
+--- a/tools/virsh-pool.c
+++ b/tools/virsh-pool.c
+@@ -1187,6 +1187,9 @@ cmdPoolList(vshControl *ctl, const vshCmd *cmd G_GNUC_UNUSED)
+             case VIR_STORAGE_POOL_VSTORAGE:
+                 flags |= VIR_CONNECT_LIST_STORAGE_POOLS_VSTORAGE;
+                 break;
+            case VIR_STORAGE_POOL_VITASTOR:
+                flags |= VIR_CONNECT_LIST_STORAGE_POOLS_VITASTOR;
+                break;
+             case VIR_STORAGE_POOL_LAST:
+                 break;
+             }
@@ -0,0 +1,39 @@
+From 98d3f68a40130c438854f61db6025f9e9b099cb6 Mon Sep 17 00:00:00 2001
+From: Vitaliy Filippov <vitalifster@gmail.com>
+Date: Sat, 20 Dec 2025 14:44:35 +0300
+Subject: [PATCH] Do not require atomic writes to be power of 2 sized and
+ aligned on length boundary
+
+It contradicts NVMe specification where alignment is only required when atomic
+write boundary (NABSPF/NABO) is set and highly limits usage of NVMe atomic writes
+
+Signed-off-by: Vitaliy Filippov <vitalifster@gmail.com>
+---
+ fs/read_write.c | 8 --------
+ 1 file changed, 8 deletions(-)
+
+diff --git a/fs/read_write.c b/fs/read_write.c
+index 833bae068770..5467d710108d 100644
+--- a/fs/read_write.c
+++ b/fs/read_write.c
+@@ -1802,17 +1802,9 @@ int generic_file_rw_checks(struct file *file_in, struct file *file_out)
+ 
+ int generic_atomic_write_valid(struct kiocb *iocb, struct iov_iter *iter)
+ {
+-	size_t len = iov_iter_count(iter);
+-
+ 	if (!iter_is_ubuf(iter))
+ 		return -EINVAL;
+ 
+-	if (!is_power_of_2(len))
+-		return -EINVAL;
+-
+-	if (!IS_ALIGNED(iocb->ki_pos, len))
+-		return -EINVAL;
+-
+ 	if (!(iocb->ki_flags & IOCB_DIRECT))
+ 		return -EOPNOTSUPP;
+ 
+-- 
+2.51.0
+
@@ -1,29 +1,172 @@
-diff --git a/src/client/qemu_driver.c b/src/client/qemu_driver.c
-index d8356dab..5f4cd50d 100644
--- a/src/client/qemu_driver.c
-+++ b/src/client/qemu_driver.c
-@@ -974,14 +974,21 @@ static void vitastor_co_read_bitmap_cb(void *opaque, long retval, uint8_t *bitma
- #endif
- }
+diff --git a/block/meson.build b/block/meson.build
+index 34b1b2a306..24ca0f1e52 100644
+--- a/block/meson.build
+++ b/block/meson.build
+@@ -114,6 +114,7 @@ foreach m : [
+   [libnfs, 'nfs', files('nfs.c')],
+   [libssh, 'ssh', files('ssh.c')],
+   [rbd, 'rbd', files('rbd.c')],
+  [vitastor, 'vitastor', files('vitastor.c')],
+ ]
+   if m[0].found()
+     module_ss = ss.source_set()
+diff --git a/meson.build b/meson.build
+index 50c774a195..e5c7a3a4b1 100644
+--- a/meson.build
+++ b/meson.build
+@@ -1652,6 +1652,26 @@ if not get_option('rbd').auto() or have_block
+   endif
+ endif
 
-static int coroutine_fn vitastor_co_block_status(
-    BlockDriverState *bs, bool want_zero, int64_t offset, int64_t bytes,
-    int64_t *pnum, int64_t *map, BlockDriverState **file)
-+static int coroutine_fn vitastor_co_block_status(BlockDriverState *bs,
-+#if QEMU_VERSION_MAJOR > 10 || QEMU_VERSION_MAJOR == 10 && QEMU_VERSION_MINOR >= 1
-+    unsigned int mode,
-+#else
-+    bool want_zero,
-+#endif
-+    int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file)
- {
-     // Allocated => return BDRV_BLOCK_DATA|BDRV_BLOCK_OFFSET_VALID
-     // Not allocated => return 0
-     // Error => return -errno
-     // Set pnum to length of the extent, `*map` = `offset`, `*file` = `bs`
-+#if QEMU_VERSION_MAJOR > 10 || QEMU_VERSION_MAJOR == 10 && QEMU_VERSION_MINOR >= 1
-+    int want_zero = (mode == BDRV_WANT_PRECISE);
-+#endif
-     VitastorRPC task;
-     VitastorClient *client = bs->opaque;
-     uint64_t inode = client->watch ? vitastor_c_inode_get_num(client->watch) : client->inode;
+vitastor = not_found
+if not get_option('vitastor').auto() or have_block
+  libvitastor_client = cc.find_library('vitastor_client', has_headers: ['vitastor_c.h'],
+    required: get_option('vitastor'))
+  if libvitastor_client.found()
+    if cc.links('''
+      #include <vitastor_c.h>
+      int main(void) {
+        vitastor_c_create_qemu(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+        return 0;
+      }''', dependencies: libvitastor_client)
+      vitastor = declare_dependency(dependencies: libvitastor_client)
+    elif get_option('vitastor').enabled()
+      error('could not link libvitastor_client')
+    else
+      warning('could not link libvitastor_client, disabling')
+    endif
+  endif
+endif
+
+ glusterfs = not_found
+ glusterfs_ftruncate_has_stat = false
+ glusterfs_iocb_has_stat = false
+@@ -2547,6 +2567,7 @@ endif
+ config_host_data.set('CONFIG_OPENGL', opengl.found())
+ config_host_data.set('CONFIG_PLUGIN', get_option('plugins'))
+ config_host_data.set('CONFIG_RBD', rbd.found())
+config_host_data.set('CONFIG_VITASTOR', vitastor.found())
+ config_host_data.set('CONFIG_RDMA', rdma.found())
+ config_host_data.set('CONFIG_RELOCATABLE', get_option('relocatable'))
+ config_host_data.set('CONFIG_SAFESTACK', get_option('safe_stack'))
+@@ -4972,6 +4993,7 @@ summary_info += {'fdt support':       fdt_opt == 'internal' ? 'internal' : fdt}
+ summary_info += {'libcap-ng support': libcap_ng}
+ summary_info += {'bpf support':       libbpf}
+ summary_info += {'rbd support':       rbd}
+summary_info += {'vitastor support':  vitastor}
+ summary_info += {'smartcard support': cacard}
+ summary_info += {'U2F support':       u2f}
+ summary_info += {'libusb':            libusb}
+diff --git a/meson_options.txt b/meson_options.txt
+index fff1521e58..f0844c0e00 100644
+--- a/meson_options.txt
+++ b/meson_options.txt
+@@ -202,6 +202,8 @@ option('pvg', type: 'feature', value: 'auto',
+        description: 'macOS paravirtualized graphics support')
+ option('rbd', type : 'feature', value : 'auto',
+        description: 'Ceph block device driver')
+option('vitastor', type : 'feature', value : 'auto',
+       description: 'Vitastor block device driver')
+ option('opengl', type : 'feature', value : 'auto',
+        description: 'OpenGL support')
+ option('rdma', type : 'feature', value : 'auto',
+diff --git a/qapi/block-core.json b/qapi/block-core.json
+index dc6eb4ae23..d043f4340e 100644
+--- a/qapi/block-core.json
+++ b/qapi/block-core.json
+@@ -3280,7 +3280,7 @@
+             'parallels', 'preallocate', 'qcow', 'qcow2', 'qed', 'quorum',
+             'raw', 'rbd',
+             { 'name': 'replication', 'if': 'CONFIG_REPLICATION' },
+-            'ssh', 'throttle', 'vdi', 'vhdx',
+            'ssh', 'throttle', 'vdi', 'vhdx', 'vitastor',
+             { 'name': 'virtio-blk-vfio-pci', 'if': 'CONFIG_BLKIO' },
+             { 'name': 'virtio-blk-vhost-user', 'if': 'CONFIG_BLKIO' },
+             { 'name': 'virtio-blk-vhost-vdpa', 'if': 'CONFIG_BLKIO' },
+@@ -4363,6 +4363,28 @@
+             '*key-secret': 'str',
+             '*server': ['InetSocketAddressBase'] } }
+ 
+##
+# @BlockdevOptionsVitastor:
+#
+# Driver specific block device options for vitastor
+#
+# @image:       Image name
+# @inode:       Inode number
+# @pool:        Pool ID
+# @size:        Desired image size in bytes
+# @config-path: Path to Vitastor configuration
+# @etcd-host:   etcd connection address(es)
+# @etcd-prefix: etcd key/value prefix
+##
+{ 'struct': 'BlockdevOptionsVitastor',
+  'data': { '*inode': 'uint64',
+            '*pool': 'uint64',
+            '*size': 'uint64',
+            '*image': 'str',
+            '*config-path': 'str',
+            '*etcd-host': 'str',
+            '*etcd-prefix': 'str' } }
+
+ ##
+ # @ReplicationMode:
+ #
+@@ -4831,6 +4853,7 @@
+       'throttle':   'BlockdevOptionsThrottle',
+       'vdi':        'BlockdevOptionsGenericFormat',
+       'vhdx':       'BlockdevOptionsGenericFormat',
+      'vitastor':   'BlockdevOptionsVitastor',
+       'virtio-blk-vfio-pci':
+                     { 'type': 'BlockdevOptionsVirtioBlkVfioPci',
+                       'if': 'CONFIG_BLKIO' },
+@@ -5304,6 +5327,20 @@
+             '*cluster-size' :   'size',
+             '*encrypt' :        'RbdEncryptionCreateOptions' } }
+ 
+##
+# @BlockdevCreateOptionsVitastor:
+#
+# Driver specific image creation options for Vitastor.
+#
+# @location: Where to store the new image file.  This location cannot
+#     point to a snapshot.
+#
+# @size: Size of the virtual disk in bytes
+##
+{ 'struct': 'BlockdevCreateOptionsVitastor',
+  'data': { 'location':         'BlockdevOptionsVitastor',
+            'size':             'size' } }
+
+ ##
+ # @BlockdevVmdkSubformat:
+ #
+@@ -5526,6 +5563,7 @@
+       'ssh':            'BlockdevCreateOptionsSsh',
+       'vdi':            'BlockdevCreateOptionsVdi',
+       'vhdx':           'BlockdevCreateOptionsVhdx',
+      'vitastor':       'BlockdevCreateOptionsVitastor',
+       'vmdk':           'BlockdevCreateOptionsVmdk',
+       'vpc':            'BlockdevCreateOptionsVpc'
+   } }
+diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
+index 0ebe6bc52a..2c37ad3892 100644
+--- a/scripts/meson-buildoptions.sh
+++ b/scripts/meson-buildoptions.sh
+@@ -175,6 +175,7 @@ meson_options_help() {
+   printf "%s\n" '  qga-vss         build QGA VSS support (broken with MinGW)'
+   printf "%s\n" '  qpl             Query Processing Library support'
+   printf "%s\n" '  rbd             Ceph block device driver'
+  printf "%s\n" '  vitastor        Vitastor block device driver'
+   printf "%s\n" '  rdma            Enable RDMA-based migration'
+   printf "%s\n" '  replication     replication support'
+   printf "%s\n" '  rust            Rust support'
+@@ -459,6 +460,8 @@ _meson_option_parse() {
+     --disable-qpl) printf "%s" -Dqpl=disabled ;;
+     --enable-rbd) printf "%s" -Drbd=enabled ;;
+     --disable-rbd) printf "%s" -Drbd=disabled ;;
+    --enable-vitastor) printf "%s" -Dvitastor=enabled ;;
+    --disable-vitastor) printf "%s" -Dvitastor=disabled ;;
+     --enable-rdma) printf "%s" -Drdma=enabled ;;
+     --disable-rdma) printf "%s" -Drdma=disabled ;;
+     --enable-relocatable) printf "%s" -Drelocatable=true ;;
@@ -0,0 +1,172 @@
+diff --git a/block/meson.build b/block/meson.build
+index 34b1b2a306..24ca0f1e52 100644
+--- a/block/meson.build
+++ b/block/meson.build
+@@ -114,6 +114,7 @@ foreach m : [
+   [libnfs, 'nfs', files('nfs.c')],
+   [libssh, 'ssh', files('ssh.c')],
+   [rbd, 'rbd', files('rbd.c')],
+  [vitastor, 'vitastor', files('vitastor.c')],
+ ]
+   if m[0].found()
+     module_ss = ss.source_set()
+diff --git a/meson.build b/meson.build
+index d9293294d8..776a5becc6 100644
+--- a/meson.build
+++ b/meson.build
+@@ -1665,6 +1665,26 @@ if not get_option('rbd').auto() or have_block
+   endif
+ endif
+ 
+vitastor = not_found
+if not get_option('vitastor').auto() or have_block
+  libvitastor_client = cc.find_library('vitastor_client', has_headers: ['vitastor_c.h'],
+    required: get_option('vitastor'))
+  if libvitastor_client.found()
+    if cc.links('''
+      #include <vitastor_c.h>
+      int main(void) {
+        vitastor_c_create_qemu(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+        return 0;
+      }''', dependencies: libvitastor_client)
+      vitastor = declare_dependency(dependencies: libvitastor_client)
+    elif get_option('vitastor').enabled()
+      error('could not link libvitastor_client')
+    else
+      warning('could not link libvitastor_client, disabling')
+    endif
+  endif
+endif
+
+ glusterfs = not_found
+ glusterfs_ftruncate_has_stat = false
+ glusterfs_iocb_has_stat = false
+@@ -2509,6 +2529,7 @@ endif
+ config_host_data.set('CONFIG_OPENGL', opengl.found())
+ config_host_data.set('CONFIG_PLUGIN', get_option('plugins'))
+ config_host_data.set('CONFIG_RBD', rbd.found())
+config_host_data.set('CONFIG_VITASTOR', vitastor.found())
+ config_host_data.set('CONFIG_RDMA', rdma.found())
+ config_host_data.set('CONFIG_RELOCATABLE', get_option('relocatable'))
+ config_host_data.set('CONFIG_SAFESTACK', get_option('safe_stack'))
+@@ -4948,6 +4969,7 @@ summary_info += {'fdt support':       fdt_opt == 'internal' ? 'internal' : fdt}
+ summary_info += {'libcap-ng support': libcap_ng}
+ summary_info += {'bpf support':       libbpf}
+ summary_info += {'rbd support':       rbd}
+summary_info += {'vitastor support':  vitastor}
+ summary_info += {'smartcard support': cacard}
+ summary_info += {'U2F support':       u2f}
+ summary_info += {'libusb':            libusb}
+diff --git a/meson_options.txt b/meson_options.txt
+index 2836156257..148086cc6f 100644
+--- a/meson_options.txt
+++ b/meson_options.txt
+@@ -206,6 +206,8 @@ option('pvg', type: 'feature', value: 'auto',
+        description: 'macOS paravirtualized graphics support')
+ option('rbd', type : 'feature', value : 'auto',
+        description: 'Ceph block device driver')
+option('vitastor', type : 'feature', value : 'auto',
+       description: 'Vitastor block device driver')
+ option('opengl', type : 'feature', value : 'auto',
+        description: 'OpenGL support')
+ option('rdma', type : 'feature', value : 'auto',
+diff --git a/qapi/block-core.json b/qapi/block-core.json
+index b82af74256..f25a6f5ce8 100644
+--- a/qapi/block-core.json
+++ b/qapi/block-core.json
+@@ -3351,7 +3351,7 @@
+             'parallels', 'preallocate', 'qcow', 'qcow2', 'qed', 'quorum',
+             'raw', 'rbd',
+             { 'name': 'replication', 'if': 'CONFIG_REPLICATION' },
+-            'ssh', 'throttle', 'vdi', 'vhdx',
+            'ssh', 'throttle', 'vdi', 'vhdx', 'vitastor',
+             { 'name': 'virtio-blk-vfio-pci', 'if': 'CONFIG_BLKIO' },
+             { 'name': 'virtio-blk-vhost-user', 'if': 'CONFIG_BLKIO' },
+             { 'name': 'virtio-blk-vhost-vdpa', 'if': 'CONFIG_BLKIO' },
+@@ -4434,6 +4434,28 @@
+             '*key-secret': 'str',
+             '*server': ['InetSocketAddressBase'] } }
+ 
+##
+# @BlockdevOptionsVitastor:
+#
+# Driver specific block device options for vitastor
+#
+# @image:       Image name
+# @inode:       Inode number
+# @pool:        Pool ID
+# @size:        Desired image size in bytes
+# @config-path: Path to Vitastor configuration
+# @etcd-host:   etcd connection address(es)
+# @etcd-prefix: etcd key/value prefix
+##
+{ 'struct': 'BlockdevOptionsVitastor',
+  'data': { '*inode': 'uint64',
+            '*pool': 'uint64',
+            '*size': 'uint64',
+            '*image': 'str',
+            '*config-path': 'str',
+            '*etcd-host': 'str',
+            '*etcd-prefix': 'str' } }
+
+ ##
+ # @ReplicationMode:
+ #
+@@ -4902,6 +4924,7 @@
+       'throttle':   'BlockdevOptionsThrottle',
+       'vdi':        'BlockdevOptionsGenericFormat',
+       'vhdx':       'BlockdevOptionsGenericFormat',
+      'vitastor':   'BlockdevOptionsVitastor',
+       'virtio-blk-vfio-pci':
+                     { 'type': 'BlockdevOptionsVirtioBlkVfioPci',
+                       'if': 'CONFIG_BLKIO' },
+@@ -5376,6 +5399,20 @@
+             '*cluster-size' :   'size',
+             '*encrypt' :        'RbdEncryptionCreateOptions' } }
+ 
+##
+# @BlockdevCreateOptionsVitastor:
+#
+# Driver specific image creation options for Vitastor.
+#
+# @location: Where to store the new image file.  This location cannot
+#     point to a snapshot.
+#
+# @size: Size of the virtual disk in bytes
+##
+{ 'struct': 'BlockdevCreateOptionsVitastor',
+  'data': { 'location':         'BlockdevOptionsVitastor',
+            'size':             'size' } }
+
+ ##
+ # @BlockdevVmdkSubformat:
+ #
+@@ -5598,6 +5635,7 @@
+       'ssh':            'BlockdevCreateOptionsSsh',
+       'vdi':            'BlockdevCreateOptionsVdi',
+       'vhdx':           'BlockdevCreateOptionsVhdx',
+      'vitastor':       'BlockdevCreateOptionsVitastor',
+       'vmdk':           'BlockdevCreateOptionsVmdk',
+       'vpc':            'BlockdevCreateOptionsVpc'
+   } }
+diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
+index 3d0d132344..65ee8c855e 100644
+--- a/scripts/meson-buildoptions.sh
+++ b/scripts/meson-buildoptions.sh
+@@ -177,6 +177,7 @@ meson_options_help() {
+   printf "%s\n" '  qga-vss         build QGA VSS support (broken with MinGW)'
+   printf "%s\n" '  qpl             Query Processing Library support'
+   printf "%s\n" '  rbd             Ceph block device driver'
+  printf "%s\n" '  vitastor        Vitastor block device driver'
+   printf "%s\n" '  rdma            Enable RDMA-based migration'
+   printf "%s\n" '  replication     replication support'
+   printf "%s\n" '  rust            Rust support'
+@@ -464,6 +465,8 @@ _meson_option_parse() {
+     --disable-qpl) printf "%s" -Dqpl=disabled ;;
+     --enable-rbd) printf "%s" -Drbd=enabled ;;
+     --disable-rbd) printf "%s" -Drbd=disabled ;;
+    --enable-vitastor) printf "%s" -Dvitastor=enabled ;;
+    --disable-vitastor) printf "%s" -Dvitastor=disabled ;;
+     --enable-rdma) printf "%s" -Drdma=enabled ;;
+     --disable-rdma) printf "%s" -Drdma=disabled ;;
+     --enable-relocatable) printf "%s" -Drelocatable=true ;;
@@ -21,7 +21,7 @@ rpmbuild -bp fio.spec
 cd $VITASTOR
 VER=$(grep ^Version: rpm/vitastor-$REL.spec | awk '{print $2}')
 rm -rf fio
-ln -s ~/rpmbuild/BUILD/fio*/ fio
+ln -s $(ls -d ~/rpmbuild/BUILD/fio*/ | grep -v SPECPARTS) fio
 sh copy-fio-includes.sh
 rm fio
 mv fio-copy fio
@@ -0,0 +1,17 @@
+# Build packages for AlmaLinux 10 inside a container
+# cd ..
+# docker pull --platform=linux/amd64/v2 quay.io/almalinuxorg/almalinux:10
+# docker build -t vitastor-buildenv:el10 -f rpm/vitastor-el10.Dockerfile .
+# docker run -i --rm -v ./:/root/vitastor vitastor-buildenv:el10 /root/vitastor/rpm/vitastor-build.sh
+
+FROM quay.io/almalinuxorg/almalinux:10
+
+WORKDIR /root
+
+RUN sed -i 's/enabled=0/enabled=1/' /etc/yum.repos.d/*.repo
+RUN dnf -y install epel-release dnf-plugins-core
+RUN dnf -y install https://vitastor.io/rpms/centos/10/vitastor-release-1.0-1.el10.noarch.rpm
+RUN dnf -y install gcc-c++ gperftools-devel fio nodejs rpm-build jerasure-devel isa-l-devel gf-complete-devel rdma-core-devel cmake libnl3-devel
+RUN dnf download --source fio
+RUN rpm --nomd5 -i fio*.src.rpm
+RUN cd ~/rpmbuild/SPECS && dnf builddep -y --spec fio.spec
@@ -0,0 +1,198 @@
+Name:           vitastor
+Version:        3.0.15
+Release:        1%{?dist}
+Summary:        Vitastor, a fast software-defined clustered block storage
+
+License:        Vitastor Network Public License 1.1
+URL:            https://vitastor.io/
+Source0:        vitastor-3.0.15.el10.tar.gz
+
+BuildRequires:  gperftools-devel
+BuildRequires:  gcc-c++
+BuildRequires:  nodejs >= 10
+BuildRequires:  jerasure-devel
+BuildRequires:  isa-l-devel
+BuildRequires:  gf-complete-devel
+BuildRequires:  rdma-core-devel
+BuildRequires:  cmake
+BuildRequires:  libnl3-devel
+Requires:       vitastor-osd = %{version}-%{release}
+Requires:       vitastor-mon = %{version}-%{release}
+Requires:       vitastor-client = %{version}-%{release}
+Requires:       vitastor-client-devel = %{version}-%{release}
+Requires:       vitastor-fio = %{version}-%{release}
+
+%description
+Vitastor is a small, simple and fast clustered block storage (storage for VM drives),
+architecturally similar to Ceph which means strong consistency, primary-replication,
+symmetric clustering and automatic data distribution over any number of drives of any
+size with configurable redundancy (replication or erasure codes/XOR).
+
+
+%package -n vitastor-osd
+Summary:        Vitastor - OSD
+Requires:       vitastor-client = %{version}-%{release}
+Requires:       util-linux
+Requires:       parted
+
+
+%description -n vitastor-osd
+Vitastor object storage daemon, i.e. server program that stores data.
+
+
+%package -n vitastor-mon
+Summary:        Vitastor - monitor
+Requires:       nodejs >= 10
+Requires:       lpsolve
+
+
+%description -n vitastor-mon
+Vitastor monitor, i.e. server program responsible for watching cluster state and
+scheduling cluster-level operations.
+
+
+%package -n vitastor-client
+Summary:        Vitastor - client
+
+
+%description -n vitastor-client
+Vitastor client library and command-line interface.
+
+
+%package -n vitastor-client-devel
+Summary:        Vitastor - development files
+Group:          Development/Libraries
+Requires:       vitastor-client = %{version}-%{release}
+
+
+%description -n vitastor-client-devel
+Vitastor library headers for development.
+
+
+%package -n vitastor-fio
+Summary:        Vitastor - fio drivers
+Group:          Development/Libraries
+Requires:       vitastor-client = %{version}-%{release}
+Requires:       fio = 3.36-5.el10
+
+
+%description -n vitastor-fio
+Vitastor fio drivers for benchmarking.
+
+
+%package -n vitastor-opennebula
+Summary:        Vitastor for OpenNebula
+Group:          Development/Libraries
+Requires:       vitastor-client
+Requires:       jq
+Requires:       python3-lxml
+Requires:       patch
+Requires:       qemu-kvm-block-vitastor
+
+
+%description -n vitastor-opennebula
+Vitastor storage plugin for OpenNebula.
+
+
+%prep
+%setup -q
+
+
+%build
+%cmake
+%cmake_build
+
+
+%install
+rm -rf $RPM_BUILD_ROOT
+%cmake_install
+cd mon
+npm install --production
+cd ..
+mkdir -p %buildroot/usr/lib/vitastor
+cp -r mon %buildroot/usr/lib/vitastor
+mv %buildroot/usr/lib/vitastor/mon/scripts/make-etcd %buildroot/usr/lib/vitastor/mon/
+mkdir -p %buildroot/lib/systemd/system
+cp mon/scripts/vitastor.target mon/scripts/vitastor-mon.service mon/scripts/vitastor-osd@.service %buildroot/lib/systemd/system
+mkdir -p %buildroot/lib/udev/rules.d
+cp mon/scripts/90-vitastor.rules %buildroot/lib/udev/rules.d
+mkdir -p %buildroot/var/lib/one
+cp -r opennebula/remotes %buildroot/var/lib/one
+cp opennebula/install.sh %buildroot/var/lib/one/remotes/datastore/vitastor/
+mkdir -p %buildroot/etc/
+cp -r opennebula/sudoers.d %buildroot/etc/
+
+
+%files
+%doc GPL-2.0.txt VNPL-1.1.txt README.md README-ru.md
+
+
+%files -n vitastor-osd
+%_bindir/vitastor-osd
+%_bindir/vitastor-disk
+%_bindir/vitastor-dump-journal
+/lib/systemd/system/vitastor-osd@.service
+/lib/systemd/system/vitastor.target
+/lib/udev/rules.d/90-vitastor.rules
+
+
+%pre -n vitastor-osd
+groupadd -r -f vitastor 2>/dev/null ||:
+useradd -r -g vitastor -s /sbin/nologin -c "Vitastor daemons" -M -d /nonexistent vitastor 2>/dev/null ||:
+install -o vitastor -g vitastor -d /var/log/vitastor
+mkdir -p /etc/vitastor
+
+
+%files -n vitastor-mon
+/usr/lib/vitastor/mon
+/lib/systemd/system/vitastor-mon.service
+
+
+%pre -n vitastor-mon
+groupadd -r -f vitastor 2>/dev/null ||:
+useradd -r -g vitastor -s /sbin/nologin -c "Vitastor daemons" -M -d /nonexistent vitastor 2>/dev/null ||:
+mkdir -p /etc/vitastor
+mkdir -p /var/lib/vitastor
+chown vitastor:vitastor /var/lib/vitastor
+
+
+%files -n vitastor-client
+%_bindir/vitastor-nbd
+%_bindir/vitastor-ublk
+%_bindir/vitastor-nfs
+%_bindir/vitastor-cli
+%_bindir/vitastor-rm
+%_bindir/vitastor-kv
+%_bindir/vitastor-kv-stress
+%_bindir/vita
+%_libdir/libvitastor_client.so*
+%_libdir/libvitastor_kv.so*
+
+
+%files -n vitastor-client-devel
+%_includedir/vitastor_c.h
+%_includedir/vitastor_kv.h
+%_libdir/pkgconfig
+
+
+%files -n vitastor-fio
+%_libdir/libfio_vitastor.so
+%_libdir/libfio_vitastor_blk.so
+%_libdir/libfio_vitastor_sec.so
+
+
+%files -n vitastor-opennebula
+/var/lib/one
+/etc/sudoers.d/opennebula-vitastor
+
+
+%triggerin -n vitastor-opennebula -- opennebula
+[ $2 = 0 ] || exit 0
+/var/lib/one/remotes/datastore/vitastor/install.sh
+
+
+# Turn off the brp-python-bytecompile script
+%global __os_install_post %(echo '%{__os_install_post}' | sed -e 's!/usr/lib[^[:space:]]*/brp-python-bytecompile[[:space:]].*$!!g')
+
+
+%changelog
@@ -1,11 +1,11 @@
 Name:           vitastor
-Version:        3.0.0
+Version:        3.0.15
 Release:        1%{?dist}
 Summary:        Vitastor, a fast software-defined clustered block storage

 License:        Vitastor Network Public License 1.1
 URL:            https://vitastor.io/
-Source0:        vitastor-3.0.0.el7.tar.gz
+Source0:        vitastor-3.0.15.el7.tar.gz

 BuildRequires:  gperftools-devel
 BuildRequires:  devtoolset-9-gcc-c++
@@ -1,11 +1,11 @@
 Name:           vitastor
-Version:        3.0.0
+Version:        3.0.15
 Release:        1%{?dist}
 Summary:        Vitastor, a fast software-defined clustered block storage

 License:        Vitastor Network Public License 1.1
 URL:            https://vitastor.io/
-Source0:        vitastor-3.0.0.el8.tar.gz
+Source0:        vitastor-3.0.15.el8.tar.gz

 BuildRequires:  gperftools-devel
 BuildRequires:  gcc-toolset-9-gcc-c++
@@ -1,11 +1,11 @@
 Name:           vitastor
-Version:        3.0.0
+Version:        3.0.15
 Release:        1%{?dist}
 Summary:        Vitastor, a fast software-defined clustered block storage

 License:        Vitastor Network Public License 1.1
 URL:            https://vitastor.io/
-Source0:        vitastor-3.0.0.el9.tar.gz
+Source0:        vitastor-3.0.15.el9.tar.gz

 BuildRequires:  gperftools-devel
 BuildRequires:  gcc-c++
@@ -1,9 +1,8 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 2.8...3.30)

 project(vitastor)

 include(GNUInstallDirs)
-include(CTest)
 include(CheckIncludeFile)

 find_package(PkgConfig)
@@ -21,7 +20,7 @@ if("${CMAKE_INSTALL_PREFIX}" MATCHES "^/usr/local/?$")
 endif()
 set(ENABLE_COVERAGE false CACHE BOOL "Enable code coverage")

-add_definitions(-DVITASTOR_VERSION="3.0.0")
+add_definitions(-DVITASTOR_VERSION="3.0.15")
 add_definitions(-D_GNU_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wall -Wno-sign-compare -Wno-comment -Wno-parentheses -Wno-pointer-arith -fdiagnostics-color=always -fno-omit-frame-pointer -fvisibility=hidden -I ${CMAKE_SOURCE_DIR}/src)
 add_link_options(-fno-omit-frame-pointer)
 if (${WITH_ASAN})
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 2.8...3.30)

 project(vitastor)

@@ -183,6 +183,11 @@ public:
    // Update configuration
    virtual void parse_config(blockstore_config_t & config) = 0;

+    // Reshard database for a pool in chunks
+    // MUST be called only when nobody makes any modifications to the DB for this pool
+    virtual void* reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit) = 0;
+    virtual bool reshard_continue(void *reshard_state, uint64_t chunk_limit) = 0;
+
    // Event loop
    virtual void loop() = 0;

@@ -223,4 +228,9 @@ public:
    virtual uint64_t get_journal_size() = 0;

    virtual uint32_t get_bitmap_granularity() = 0;
+
+    virtual uint64_t get_live_entries() = 0;
+    virtual uint64_t get_live_memory() = 0;
+    virtual uint64_t get_garbage_entries() = 0;
+    virtual uint64_t get_garbage_memory() = 0;
 };
@@ -94,6 +94,9 @@ void blockstore_disk_t::parse_config(std::map<std::string, std::string> & config
    csum_block_size = parse_size(config["csum_block_size"]);
    discard_on_start = config.find("discard_on_start") != config.end() &&
        (config["discard_on_start"] == "true" || config["discard_on_start"] == "1" || config["discard_on_start"] == "yes");
+    gc_on_start = config.find("gc_on_start") == config.end() ||
+        (config["gc_on_start"] == "true" || config["gc_on_start"] == "1" || config["gc_on_start"] == "yes");
+    skip_double_claim = (config["skip_double_claim"] == "true" || config["skip_double_claim"] == "1" || config["skip_double_claim"] == "yes");
    min_discard_size = parse_size(config["min_discard_size"]);
    if (!min_discard_size)
        min_discard_size = 1024*1024;
@@ -171,6 +174,10 @@ void blockstore_disk_t::parse_config(std::map<std::string, std::string> & config
    {
        throw std::runtime_error("Data block size must be a multiple of sparse write tracking granularity");
    }
+    if (data_block_size / bitmap_granularity < 8)
+    {
+        throw std::runtime_error("Data block size must be at least bitmap_granularity*8");
+    }
    if (!data_csum_type)
    {
        csum_block_size = 0;
@@ -259,7 +266,7 @@ void blockstore_disk_t::calc_lengths(bool skip_meta_check)
    }
    // required metadata size
    block_count = data_len / data_block_size;
-    clean_entry_bitmap_size = data_block_size / bitmap_granularity / 8;
+    clean_entry_bitmap_size = (data_block_size / bitmap_granularity + 7) / 8;
    clean_dyn_size = clean_entry_bitmap_size*2 + (csum_block_size
        ? data_block_size/csum_block_size*(data_csum_type & 0xFF) : 0);
 recalc:
@@ -510,7 +517,7 @@ void blockstore_disk_t::close_all()

 // Sadly DISCARD only works through ioctl(), but it seems to always block the device queue,
 // so it's not a big deal that we can only run it synchronously.
-int blockstore_disk_t::trim_data(std::function<bool(uint64_t)> is_free)
+int blockstore_disk_t::trim_data(std::function<bool(uint64_t)> is_used)
 {
    if (mock_mode)
    {
@@ -521,7 +528,7 @@ int blockstore_disk_t::trim_data(std::function<bool(uint64_t)> is_free)
    uint64_t discarded = 0;
    for (; i <= block_count; i++)
    {
-        if (i >= block_count || is_free(i))
+        if (i >= block_count || is_used(i))
        {
            if (i > j && (i-j)*data_block_size >= min_discard_size)
            {
@@ -534,17 +541,21 @@ int blockstore_disk_t::trim_data(std::function<bool(uint64_t)> is_free)
                    if (range[0] % discard_granularity)
                        range[0] = range[0] + discard_granularity - (range[0] % discard_granularity);
                    if (range[0] >= range[1])
-                        continue;
-                    range[1] -= range[0];
+                        range[1] = 0;
+                    else
+                        range[1] -= range[0];
                }
-                r = ioctl(data_fd, BLKDISCARD, &range);
-                if (r != 0)
+                if (range[1] > 0)
                {
-                    fprintf(stderr, "Failed to execute BLKDISCARD %ju+%ju on %s: %s (code %d)\n",
-                        range[0], range[1], data_device.c_str(), strerror(-r), r);
-                    return -errno;
+                    r = ioctl(data_fd, BLKDISCARD, &range);
+                    if (r != 0)
+                    {
+                        fprintf(stderr, "Failed to execute BLKDISCARD %ju+%ju on %s: %s (code %d)\n",
+                            range[0], range[1], data_device.c_str(), strerror(-r), r);
+                        return -errno;
+                    }
+                    discarded += range[1];
                }
-                discarded += range[1];
            }
            j = i+1;
        }
@@ -26,14 +26,14 @@ class allocator_t;
 struct blockstore_disk_t
 {
    std::string data_device, meta_device, journal_device;
-    uint32_t data_block_size;
+    uint64_t data_block_size;
    uint64_t cfg_journal_size, cfg_data_size;
    // Required write alignment and journal/metadata/data areas' location alignment
    uint32_t disk_alignment = 4096;
    // Journal block size - minimum_io_size of the journal device is the best choice
-    uint32_t journal_block_size = 4096;
+    uint64_t journal_block_size = 4096;
    // Metadata block size - minimum_io_size of the metadata device is the best choice
-    uint32_t meta_block_size = 4096;
+    uint64_t meta_block_size = 4096;
    // Atomic write size of the data block device
    uint32_t atomic_write_size = 4096;
    // Whether we should set RWF_ATOMIC on atomic writes
@@ -57,6 +57,10 @@ struct blockstore_disk_t
    bool inmemory_journal = true;
    // Data discard granularity and minimum size (for the sake of performance)
    bool discard_on_start = false;
+    // GC on start (new store)
+    bool gc_on_start = true;
+    // Skip double claim conflicts on start (new store, temporary until the bug is found)
+    bool skip_double_claim = false;
    uint64_t min_discard_size = 1024*1024;
    uint64_t discard_granularity = 0;

@@ -79,7 +83,7 @@ struct blockstore_disk_t
    void calc_lengths(bool skip_meta_check = false);
    void check_lengths();
    void close_all();
-    int trim_data(std::function<bool(uint64_t)> is_free);
+    int trim_data(std::function<bool(uint64_t)> is_used);

    inline uint64_t dirty_dyn_size(uint64_t offset, uint64_t len)
    {
@@ -174,14 +174,18 @@ bool journal_flusher_co::loop()
    else if (wait_state == 19) goto resume_19;
    else if (wait_state == 20) goto resume_20;
    else if (wait_state == 21) goto resume_21;
+    else if (wait_state == 22) goto resume_22;
+    else if (wait_state == 23) goto resume_23;
+    else if (wait_state == 24) goto resume_24;
+    else if (wait_state == 25) goto resume_25;
 resume_0:
    wait_state = 0;
    wait_count = 0;
    cur_oid = {};
    res = bs->heap->get_next_compact(cur_oid);
-    // Advance fsynced_lsn every <journal_trim_interval> intent writes
    if ((bs->intent_write_counter >= bs->journal_trim_interval) && co_id == 0)
    {
+        // Advance fsynced_lsn every <journal_trim_interval> intent writes
        bs->intent_write_counter = 0;
 resume_17:
 resume_18:
@@ -196,6 +200,7 @@ resume_21:
    if (res == ENOENT && flusher->force_start > 0 && co_id == 0 &&
        (!bs->dsk.disable_journal_fsync || !bs->dsk.disable_meta_fsync || !bs->dsk.disable_data_fsync))
    {
+        // When under pressure, do an additional fsync to force entries to be marked compactable
        flusher->active_flushers++;
 resume_14:
 resume_15:
@@ -259,11 +264,9 @@ resume_1:
        if (wr->type() == BS_HEAP_SMALL_WRITE ||
            wr->type() == BS_HEAP_INTENT_WRITE && bs->dsk.csum_block_size > bs->dsk.bitmap_granularity)
        {
-            auto res = bs->prepare_read(read_vec, cur_obj, wr, 0, bs->dsk.data_block_size,
+            bs->prepare_read(read_vec, cur_obj, wr, 0, bs->dsk.data_block_size,
                wr->type() == BS_HEAP_INTENT_WRITE && bs->dsk.csum_block_size > bs->dsk.bitmap_granularity && !bs->perfect_csum_update
                ? COPY_BUF_SKIP_CSUM : 0);
-            if (res > 0)
-                copy_count++;
        }
    });
    if (!compact_info.compact_lsn)
@@ -273,30 +276,53 @@ resume_1:
        bs->heap->unlock_entry(cur_oid);
        goto resume_0;
    }
-    mem_or(new_bmp, compact_info.clean_wr->get_int_bitmap(bs->heap), bs->dsk.clean_entry_bitmap_size);
-    if (!bitmap_copied)
-    {
-        memcpy(new_ext_bmp, compact_info.clean_wr->get_ext_bitmap(bs->heap), bs->dsk.clean_entry_bitmap_size);
-        bitmap_copied = true;
-    }
-    if (bs->dsk.csum_block_size && bs->dsk.csum_block_size <= bs->dsk.bitmap_granularity)
-    {
-        memcpy(new_csums, compact_info.clean_wr->get_checksums(bs->heap), bs->dsk.data_block_size/bs->dsk.csum_block_size * (bs->dsk.data_csum_type & 0xFF));
-        for (size_t i = csum_copy.size(); i > 0; i--)
-        {
-            auto wr = csum_copy[i-1];
-            memcpy(new_csums + wr->small().offset/bs->dsk.csum_block_size*(bs->dsk.data_csum_type & 0xFF),
-                wr->get_checksums(bs->heap), wr->small().len/bs->dsk.csum_block_size*(bs->dsk.data_csum_type & 0xFF));
-        }
-        csum_copy.clear();
-    }
-    clean_loc = compact_info.clean_wr->big_location(bs->heap);
    flusher->active_flushers++;
-    if (bs->log_level > 10)
+    for (i = 0; i < read_vec.size(); i++)
    {
-        printf("Compacting %jx:%jx v%ju..v%ju / l%ju..l%ju (%d writes)\n", cur_oid.inode, cur_oid.stripe,
-            compact_info.clean_wr->version, compact_info.compact_version,
-            compact_info.clean_wr->lsn, compact_info.compact_lsn, copy_count);
+        if ((read_vec[i].copy_flags & COPY_BUF_JOURNAL) &&
+            !(read_vec[i].copy_flags & COPY_BUF_COALESCED))
+        {
+            copy_count++;
+        }
+    }
+    if (copy_count > 0 && !bs->dsk.disable_data_fsync)
+    {
+        init_fsync_data();
+    }
+    if (compact_info.do_delete)
+    {
+        if (bs->log_level > 10)
+        {
+            printf("Compacting %jx:%jx up to l%ju (delete)\n", cur_oid.inode, cur_oid.stripe, compact_info.compact_lsn);
+        }
+        clean_loc = UINT64_MAX;
+    }
+    else
+    {
+        if (bs->log_level > 10)
+        {
+            printf("Compacting %jx:%jx v%ju..v%ju / l%ju..l%ju (%d writes)\n", cur_oid.inode, cur_oid.stripe,
+                compact_info.clean_wr->version, compact_info.compact_version,
+                compact_info.clean_wr->lsn, compact_info.compact_lsn, copy_count);
+        }
+        mem_or(new_bmp, compact_info.clean_wr->get_int_bitmap(bs->heap), bs->dsk.clean_entry_bitmap_size);
+        if (!bitmap_copied)
+        {
+            memcpy(new_ext_bmp, compact_info.clean_wr->get_ext_bitmap(bs->heap), bs->dsk.clean_entry_bitmap_size);
+            bitmap_copied = true;
+        }
+        if (bs->dsk.csum_block_size && bs->dsk.csum_block_size <= bs->dsk.bitmap_granularity)
+        {
+            memcpy(new_csums, compact_info.clean_wr->get_checksums(bs->heap), bs->dsk.data_block_size/bs->dsk.csum_block_size * (bs->dsk.data_csum_type & 0xFF));
+            for (size_t i = csum_copy.size(); i > 0; i--)
+            {
+                auto wr = csum_copy[i-1];
+                memcpy(new_csums + wr->small().offset/bs->dsk.csum_block_size*(bs->dsk.data_csum_type & 0xFF),
+                    wr->get_checksums(bs->heap), wr->small().len/bs->dsk.csum_block_size*(bs->dsk.data_csum_type & 0xFF));
+            }
+            csum_copy.clear();
+        }
+        clean_loc = compact_info.clean_wr->big_location(bs->heap);
    }
    overwrite_start = overwrite_end = 0;
    if (read_vec.size() > 0)
@@ -336,6 +362,13 @@ resume_3:
    if (res == ENOENT || res == EDOM)
    {
        // Abort compaction
+abort_compact:
+        if (copy_count > 0 && !bs->dsk.disable_data_fsync)
+        {
+            cur_sync->member_count--;
+            if (cur_sync->member_count > 0)
+                bs->ringloop->wakeup();
+        }
        flusher->flushing.erase(cur_oid);
        bs->heap->unlock_entry(cur_oid);
        flusher->active_flushers--;
@@ -349,10 +382,7 @@ resume_4:
        if (res == ENOENT)
        {
            // Abort compaction
-            flusher->flushing.erase(cur_oid);
-            bs->heap->unlock_entry(cur_oid);
-            flusher->active_flushers--;
-            goto resume_0;
+            goto abort_compact;
        }
        if (res == EAGAIN)
        {
@@ -381,14 +411,14 @@ resume_9:
    for (i = 0; i < read_vec.size(); i++)
    {
        if ((read_vec[i].copy_flags & COPY_BUF_JOURNAL) &&
-            !(read_vec[i].copy_flags & COPY_BUF_COALESCED) ||
-            (read_vec[i].copy_flags & COPY_BUF_PADDED)) // FIXME Shit, simplify these flags
+            !(read_vec[i].copy_flags & COPY_BUF_COALESCED))
        {
            assert(read_vec[i].buf);
            await_sqe(10);
            data->iov = (struct iovec){ read_vec[i].buf + (read_vec[i].copy_flags & COPY_BUF_PADDED
                ? read_vec[i].offset - read_vec[i].disk_offset : 0), (size_t)read_vec[i].len };
            data->callback = simple_callback_w;
+            assert(clean_loc + read_vec[i].offset + data->iov.iov_len <= bs->dsk.block_count*bs->dsk.data_block_size);
            io_uring_prep_writev(sqe, bs->dsk.data_fd, &data->iov, 1, bs->dsk.data_offset + clean_loc + read_vec[i].offset);
            wait_count++;
        }
@@ -399,6 +429,17 @@ resume_11:
        wait_state = 11;
        return false;
    }
+    if (copy_count > 0 && !bs->dsk.disable_data_fsync)
+    {
+resume_22:
+resume_23:
+resume_24:
+resume_25:
+        if (!fsync_data(22))
+        {
+            return false;
+        }
+    }
    // Lock is only needed to prevent freeing the big_write because we overwrite it...
    bs->heap->unlock_entry(cur_oid);
    // Mark the object compacted, but don't free and remove small_writes
@@ -408,12 +449,14 @@ resume_11:
    if (!cur_obj)
    {
        // Abort compaction
+        flusher->active_flushers--;
        flusher->flushing.erase(cur_oid);
        goto resume_0;
    }
    if (!calc_block_checksums())
    {
        // Abort compaction
+        flusher->active_flushers--;
        flusher->flushing.erase(cur_oid);
        goto resume_0;
    }
@@ -422,6 +465,7 @@ resume_11:
    if (res == EBUSY)
    {
        // Abort compaction, object is already overwritten by something else
+        flusher->active_flushers--;
        flusher->flushing.erase(cur_oid);
        goto resume_0;
    }
@@ -586,13 +630,13 @@ int journal_flusher_co::check_and_punch_checksums()
            bs->heap->calc_block_checksums((uint32_t*)(new_csums+csum_off), vec.buf, punch_bmp, vec.offset, vec.offset+vec.len, true, NULL);
        }
    }
-    // Modified, we should add_punch_holes and then write the block to disk
+    // Modified, we should punch_holes and then write the block to disk
    return EBUSY;
 }

 bool journal_flusher_co::calc_block_checksums()
 {
-    if (bs->dsk.csum_block_size <= bs->dsk.bitmap_granularity)
+    if (bs->dsk.csum_block_size <= bs->dsk.bitmap_granularity || compact_info.do_delete)
    {
        return true;
    }
@@ -699,6 +743,67 @@ resume_1:
    return true;
 }

+void journal_flusher_co::init_fsync_data()
+{
+    cur_sync = flusher->data_syncs.begin();
+    if (cur_sync == flusher->data_syncs.end() || cur_sync->ready_count > 0)
+    {
+        cur_sync = flusher->data_syncs.emplace(cur_sync);
+    }
+    cur_sync->member_count++;
+}
+
+bool journal_flusher_co::fsync_data(int wait_base)
+{
+    if (wait_state == wait_base)
+        goto resume_0;
+    else if (wait_state == wait_base+1)
+        goto resume_1;
+    else if (wait_state == wait_base+2)
+        goto resume_2;
+    else if (wait_state == wait_base+3)
+        goto resume_3;
+    cur_sync->ready_count++;
+resume_0:
+    if (cur_sync->ready_count < cur_sync->member_count)
+    {
+        wait_state = wait_base;
+        return false;
+    }
+    if (!cur_sync->sent)
+    {
+        // Sync batch is ready. Do it.
+        await_sqe(1);
+        data->iov = { 0 };
+        data->callback = simple_callback_w;
+        io_uring_prep_fsync(sqe, bs->dsk.data_fd, IORING_FSYNC_DATASYNC);
+        cur_sync->sent = true;
+        wait_count++;
+resume_2:
+        if (wait_count > 0)
+        {
+            wait_state = wait_base+2;
+            return false;
+        }
+        cur_sync->done = true;
+        // Wake up other flushers
+        bs->ringloop->wakeup();
+    }
+resume_3:
+    if (!cur_sync->done)
+    {
+        wait_state = wait_base+3;
+        return false;
+    }
+    cur_sync->done_count++;
+    if (cur_sync->done_count >= cur_sync->member_count)
+    {
+        flusher->data_syncs.erase(cur_sync);
+        cur_sync = flusher->data_syncs.end();
+    }
+    return true;
+}
+
 bool journal_flusher_co::fsync_meta(int wait_base)
 {
    if (wait_state == wait_base)        goto resume_0;
@@ -25,6 +25,15 @@ struct flusher_meta_write_t
    std::map<uint64_t, meta_sector_t>::iterator it;
 };

+struct flusher_data_sync_t
+{
+    int member_count = 0;
+    int ready_count = 0;
+    int done_count = 0;
+    bool sent = false;
+    bool done = false;
+};
+
 class journal_flusher_t;

 // Journal flusher coroutine
@@ -58,7 +67,7 @@ class journal_flusher_co
    int i, res;
    bool read_to_fill_incomplete;
    int copy_count;
-    bool do_repeat = false;
+    std::list<flusher_data_sync_t>::iterator cur_sync;

    friend class journal_flusher_t;

@@ -69,6 +78,8 @@ class journal_flusher_co
    bool calc_block_checksums();
    bool write_meta_block(int wait_base);
    bool read_buffered(int wait_base);
+    void init_fsync_data();
+    bool fsync_data(int wait_base);
    bool fsync_meta(int wait_base);
    bool fsync_buffer(int wait_base);
    bool trim_lsn(int wait_base);
@@ -89,6 +100,7 @@ class journal_flusher_t

    robin_hood::unordered_flat_set<object_id> flushing;
    int active_flushers = 0;
+    std::list<flusher_data_sync_t> data_syncs;
    int wanting_meta_fsync = 0;
    bool fsyncing_meta = false;
    int syncing_buffer = 0;
@@ -57,11 +57,11 @@ struct __attribute__((__packed__)) heap_entry_t
    inline heap_small_write_t& small() { return *(heap_small_write_t*)this; }
    inline heap_big_write_t& big() { return *(heap_big_write_t*)this; }
    inline heap_big_intent_t& big_intent() { return *(heap_big_intent_t*)this; }
-    bool is_garbage();
+    bool is_garbage() const;
    void set_garbage();
-    bool is_overwrite();
-    bool is_compactable();
-    bool is_before(heap_entry_t *other);
+    bool is_overwrite() const;
+    bool is_compactable() const;
+    bool is_before(const heap_entry_t *other) const;
    uint32_t get_size(blockstore_heap_t *heap);
    uint8_t *get_ext_bitmap(blockstore_heap_t *heap);
    uint8_t *get_int_bitmap(blockstore_heap_t *heap);
@@ -117,10 +117,13 @@ struct heap_object_mvcc_t

 struct heap_block_info_t
 {
-    uint32_t used_space = 0;
+    struct __attribute__((__packed__))
+    {
+        uint32_t used_space = 0;
+        uint32_t garbage_space = 0;
+    };
    uint64_t mod_lsn = 0, mod_lsn_to = 0; // only 1 block write of LSN sequence is allowed at a moment
-    bool is_writing: 1;
-    bool has_garbage: 1;
+    bool is_writing = false;
    std::vector<heap_list_item_t*> entries;
 };

@@ -137,6 +140,8 @@ struct heap_compact_t
    bool do_delete;
 };

+struct heap_reshard_state_t;
+
 struct heap_li_hash
 {
    size_t operator()(const heap_list_item_t* li) const noexcept
@@ -153,6 +158,16 @@ struct heap_li_equal
    }
 };

+struct heap_recheck_state_t
+{
+    heap_entry_t *obj = NULL;
+    heap_entry_t *next_wr = NULL;
+    size_t total_reads = 0;
+    size_t sent_reads = 0;
+    size_t checked_reads = 0;
+    heap_entry_t *bad_wr = NULL;
+};
+
 using i64hash_t = robin_hood::hash<uint64_t>;
 using heap_inode_map_t = robin_hood::unordered_flat_set<heap_list_item_t*, heap_li_hash, heap_li_equal, 88>;
 using heap_block_index_t = robin_hood::unordered_flat_map<uint64_t,
@@ -161,7 +176,7 @@ using heap_mvcc_map_t = robin_hood::unordered_flat_map<object_id, heap_object_mv

 class blockstore_heap_t
 {
-    friend class heap_entry_t;
+    friend struct heap_entry_t;

    blockstore_disk_t *dsk = NULL;
    uint8_t* buffer_area = NULL;
@@ -182,6 +197,11 @@ class blockstore_heap_t
    uint64_t buffer_area_used_space = 0;
    uint64_t data_used_space = 0;

+    uint64_t live_entries = 0;
+    uint64_t live_memory = 0;
+    uint64_t garbage_entries = 0;
+    uint64_t garbage_memory = 0;
+
    uint64_t next_lsn = 0;
    uint32_t last_allocated_block = UINT32_MAX;
    heap_mvcc_map_t object_mvcc;
@@ -198,29 +218,36 @@ class blockstore_heap_t

    bool marked_used_blocks = false;
    bool recheck_queue_filled = false;
+    std::vector<heap_list_item_t*> postponed_items;
+    std::vector<heap_list_item_t*> init_erase_items;
    std::set<uint32_t> recheck_modified_blocks;
    std::deque<heap_entry_t*> recheck_queue;
+    std::map<heap_entry_t*, heap_recheck_state_t> recheck_states;
+    size_t recheck_pending_reads = 0;
    int recheck_in_progress = 0;
    bool in_recheck = false;
    std::function<void(bool is_data, uint64_t offset, uint64_t len, uint8_t* buf, std::function<void()>)> recheck_cb;
    int recheck_queue_depth = 0;

-    void inode_map_put(void* & inode_idx, heap_list_item_t* li);
-    void inode_map_get(void *inode_idx, heap_inode_map_t::iterator & li_it, heap_list_item_t* & li, uint64_t stripe);
-    void inode_map_free(void* inode_idx);
-    void inode_map_iterate(void* & inode_idx, std::function<void(heap_list_item_t*)> cb);
-    void inode_map_replace(void* & inode_idx, const heap_inode_map_t::iterator & li_it, heap_list_item_t* new_li);
-    void inode_map_erase(void* & inode_idx, const heap_inode_map_t::iterator & li_it, heap_list_item_t* li);
-
    uint64_t get_pg_id(inode_t inode, uint64_t stripe);
    bool validate_object(heap_entry_t *obj);
    void fill_recheck_queue();
+    void recheck_drop_entries(heap_entry_t *obj, heap_entry_t *bad_wr);
+    void recheck_start_reads(heap_recheck_state_t *st);
    int mark_used_blocks();
+    void init_free_bad_entry(heap_entry_t *wr);
+    void init_erase_bad_entry(heap_list_item_t *li);
+    bool init_erase_double_claim(heap_list_item_t *prev_li, heap_list_item_t *cur_li);
+    void recheck_full_gc();
    void recheck_buffer(heap_entry_t *cwr, uint8_t *buf);
    void defragment_block(uint32_t block_num);
+    void reshard_add(heap_reshard_state_t *st, heap_list_item_t *li);

+    void gc_block(heap_block_info_t & inf);
    int allocate_entry(uint32_t entry_size, uint32_t *block_num, bool allow_last_free);
-    void insert_list_item(heap_list_item_t *li);
+    void insert_list_items(heap_list_item_t** v, size_t count, bool postpone);
+    void remove_list_item(heap_list_item_t *li);
+    void unlink_list_item(heap_list_item_t *li);
    int add_entry(uint32_t wr_size, uint32_t *modified_block, bool allow_last_free,
        bool explicit_complete, std::function<void(heap_entry_t *wr)> fill_entry);
    int add_simple(heap_entry_t *obj, uint64_t version, uint32_t *modified_block, uint32_t entry_type);
@@ -241,28 +268,29 @@ public:
        std::function<void(uint32_t, uint32_t, uint8_t*)> handle_block);
    int load_blocks(uint64_t disk_offset, uint64_t size, uint8_t *buf,
        bool allow_corrupted, uint64_t &entries_loaded);
-    // finish loading
-    int finish_load(bool allow_corrupted = false);
+    // finish loading - should be called after load_blocks
+    void finish_load();
    // get blocks which are modified during loading and should be written to the disk
    // before finishing initialization if not R/O
    std::vector<uint32_t> get_recheck_modified_blocks();
    // recheck small write data after reading the database from disk
    bool recheck_small_writes(std::function<void(bool is_data, uint64_t offset, uint64_t len, uint8_t* buf, std::function<void()>)> read_buffer, int queue_depth);
+    int finish_recheck();
    // reshard database according to the pool's PG count
-    void reshard(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size);
+    void* reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit);
+    bool reshard_continue(void* reshard_state, uint64_t chunk_limit);
+    bool reshard_check(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size);
    void set_no_inode_stats(const std::vector<uint64_t> & pool_ids);
    void recalc_inode_space_stats(uint64_t pool_id, bool per_inode);
    // read an object entry and lock it against removal
    // in the future, may become asynchronous
    heap_entry_t *lock_and_read_entry(object_id oid);
-    // re-read a locked object entry with the given lsn (pointer may be invalidated)
-    heap_entry_t *read_locked_entry(object_id oid, uint64_t lsn);
    // read an object entry without locking it
    heap_entry_t *read_entry(object_id oid);
    // unlock an entry
    bool unlock_entry(object_id oid);
    // set or verify checksums in a write request
-    bool calc_checksums(heap_entry_t *wr, uint8_t *data, bool set, uint32_t offset = 0, uint32_t len = 0);
+    bool calc_checksums(heap_entry_t *wr, uint8_t *data, bool set, uint32_t offset = UINT32_MAX, uint32_t len = UINT32_MAX);
    // set or verify raw block checksums
    bool calc_block_checksums(uint32_t *block_csums, uint8_t *data, uint8_t *bitmap, uint32_t start, uint32_t end,
        bool set, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb);
@@ -314,6 +342,7 @@ public:
    void start_block_write(uint32_t block_num);
    void complete_block_write(uint32_t block_num);
    void complete_lsn_write(uint64_t lsn);
+    bool is_lsn_completed(uint64_t lsn);
    uint64_t get_completed_lsn();
    uint64_t get_fsynced_lsn();
    void mark_lsn_fsynced(uint64_t lsn);
@@ -333,7 +362,7 @@ public:

    // get metadata block data buffer and used space
    void get_meta_block(uint32_t block_num, uint8_t *buffer);
-    void fill_block_empty_space(uint8_t *buffer, uint32_t pos);
+    void fill_block_empty_space(uint8_t *buffer, uint64_t pos);
    uint32_t get_meta_block_used_space(uint32_t block_num);

    // get space usage statistics
@@ -345,6 +374,10 @@ public:
    uint32_t get_compact_queue_size();
    uint32_t get_to_compact_count();
    uint64_t get_compacted_count();
+    uint64_t get_live_entries();
+    uint64_t get_live_memory();
+    uint64_t get_garbage_entries();
+    uint64_t get_garbage_memory();

    uint64_t entry_pos(uint32_t block_num, uint32_t offset);
    heap_entry_t *entry_from_pos(uint64_t entry_pos, bool allow_unallocated = false);
@@ -23,6 +23,7 @@ blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_i *
        dsk.open_meta();
        dsk.open_journal();
        dsk.calc_lengths();
+        dsk.check_lengths();
    }
    catch (std::exception & e)
    {
@@ -31,16 +32,13 @@ blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_i *
    }
    meta_superblock = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, dsk.meta_block_size);
    memset(meta_superblock, 0, dsk.meta_block_size);
-}
-
-void blockstore_impl_t::init()
-{
    flusher = new journal_flusher_t(this);
    if (dsk.inmemory_journal)
    {
        buffer_area = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, dsk.journal_len);
    }
    heap = new blockstore_heap_t(&dsk, buffer_area, log_level);
+    ringloop->wakeup();
 }

 blockstore_impl_t::~blockstore_impl_t()
@@ -103,6 +101,7 @@ void blockstore_impl_t::loop()
        unsigned initial_ring_space = ringloop->space_left();
        int op_idx = 0, new_idx = 0;
        bool has_unfinished_writes = false;
+        bool has_unfinished_sync = false;
        for (; op_idx < submit_queue.size(); op_idx++, new_idx++)
        {
            auto op = submit_queue[op_idx];
@@ -140,7 +139,13 @@ void blockstore_impl_t::loop()
            else if (op->opcode == BS_OP_SYNC)
            {
                // syncs only completed writes, so doesn't have to be blocked by anything
-                wr_st = continue_sync(op);
+                if (!has_unfinished_sync)
+                {
+                    wr_st = continue_sync(op);
+                    has_unfinished_sync = (wr_st != 2);
+                }
+                else
+                    wr_st = 0;
            }
            else if (op->opcode == BS_OP_STABLE || op->opcode == BS_OP_ROLLBACK)
            {
@@ -156,9 +161,7 @@ void blockstore_impl_t::loop()
                    wr_st = 2;
                }
                else
-                {
                    wr_st = 0;
-                }
            }
            if (wr_st == 2)
            {
@@ -195,12 +198,12 @@ void blockstore_impl_t::loop()
            heap->start_block_write(block_num);
            mb.sent = true;
        }
+        pending_modified_blocks.clear();
        int ret = ringloop->submit();
        if (ret < 0)
        {
            throw std::runtime_error(std::string("io_uring_submit: ") + strerror(-ret));
        }
-        pending_modified_blocks.clear();
        if ((initial_ring_space - ringloop->space_left()) > 0)
        {
            live = true;
@@ -325,9 +328,13 @@ void blockstore_impl_t::process_list(blockstore_op_t *op)
        FINISH_OP(op);
        return;
    }
-    // Check if the DB needs resharding
-    // (we don't know about PGs from the beginning, we only create "shards" here)
-    heap->reshard(INODE_POOL(min_inode), pg_count, pg_stripe_size);
+    // Check if the DB is sharded correctly
+    if (!heap->reshard_check(INODE_POOL(min_inode), pg_count, pg_stripe_size))
+    {
+        op->retval = -EAGAIN;
+        FINISH_OP(op);
+        return;
+    }
    obj_ver_id *result = NULL;
    size_t stable_count = 0, unstable_count = 0;
    int res = heap->list_objects(list_pg, op->min_oid, op->max_oid, &result, &stable_count, &unstable_count);
@@ -394,3 +401,13 @@ std::string blockstore_impl_t::get_op_diag(blockstore_op_t *op)
        snprintf(buf, sizeof(buf), "state=%d", priv->op_state);
    return std::string(buf);
 }
+
+void* blockstore_impl_t::reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit)
+{
+    return heap->reshard_start(pool, pg_count, pg_stripe_size, chunk_limit);
+}
+
+bool blockstore_impl_t::reshard_continue(void *reshard_state, uint64_t chunk_limit)
+{
+    return heap->reshard_continue(reshard_state, chunk_limit);
+}
@@ -78,6 +78,7 @@ public:
    // Suitable only for server SSDs with capacitors, requires disabled data and journal fsyncs
    int immediate_commit = IMMEDIATE_NONE;
    bool inmemory_meta = false;
+    bool skip_corrupted_meta_entries = false;
    uint32_t meta_write_recheck_parallelism = 0;
    // Maximum and minimum flusher count
    unsigned max_flusher_count = 0, min_flusher_count = 0;
@@ -116,9 +117,12 @@ public:

    journal_flusher_t *flusher;
    int write_iodepth = 0;
-    int inflight_big = 0;
    int intent_write_counter = 0;
-    bool fsyncing_data = false;
+    uint64_t data_fsync_next = 0;
+    uint64_t data_fsync_cur = 0;
+    uint64_t data_fsync_sent = 0;
+    uint64_t data_fsync_done = 0;
+    std::deque<bool> data_fsyncs;

    bool live = false, queue_stall = false;
    ring_loop_i *ringloop = NULL;
@@ -142,7 +146,6 @@ public:
    int metadata_buf_size;
    blockstore_init_meta* metadata_init_reader;

-    void init();
    void check_wait(blockstore_op_t *op);
    void init_op(blockstore_op_t *op);

@@ -190,6 +193,9 @@ public:
    void parse_config(blockstore_config_t & config);
    void parse_config(blockstore_config_t & config, bool init);

+    void* reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit);
+    bool reshard_continue(void *reshard_state, uint64_t chunk_limit);
+
    // Event loop
    void loop();

@@ -226,4 +232,9 @@ public:
    uint64_t get_free_block_count();
    inline uint32_t get_bitmap_granularity() { return dsk.bitmap_granularity; }
    inline uint64_t get_journal_size() { return dsk.journal_len; }
+
+    inline uint64_t get_live_entries() { return heap->get_live_entries(); }
+    inline uint64_t get_live_memory() { return heap->get_live_memory(); }
+    inline uint64_t get_garbage_entries() { return heap->get_garbage_entries(); }
+    inline uint64_t get_garbage_memory() { return heap->get_garbage_memory(); }
 };
@@ -10,7 +10,6 @@
 #define INIT_META_EMPTY 0
 #define INIT_META_READING 1
 #define INIT_META_READ_DONE 2
-#define INIT_META_WRITING 3

 #define GET_SQE() \
    sqe = bs->get_sqe();\
@@ -23,14 +22,15 @@ blockstore_init_meta::blockstore_init_meta(blockstore_impl_t *bs)
    this->bs = bs;
 }

-void blockstore_init_meta::handle_event(ring_data_t *data, int buf_num)
+void blockstore_init_meta::handle_event(ring_data_t *data, int buf_num, const char *op)
 {
-    if (data->res < 0)
+    if (data->res != data->iov.iov_len)
    {
-        throw std::runtime_error(
-            std::string("read metadata failed at offset ") + std::to_string(buf_num >= 0 ? bufs[buf_num].offset : last_read_offset) +
-            std::string(": ") + strerror(-data->res)
-        );
+        throw std::runtime_error(strprintf(
+            "%s failed at offset %ju: got %s (code %d), but expected %zu",
+            op, (buf_num >= 0 ? bufs[buf_num].offset : last_read_offset), strerror(-data->res),
+            data->res, data->iov.iov_len
+        ));
    }
    if (buf_num >= 0)
    {
@@ -60,7 +60,7 @@ int blockstore_init_meta::loop()
    GET_SQE();
    last_read_offset = 0;
    data->iov = { bs->meta_superblock, (size_t)bs->dsk.meta_block_size };
-    data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
+    data->callback = [this](ring_data_t *data) { handle_event(data, -1, "read metadata header"); };
    io_uring_prep_readv(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset);
    bs->ringloop->submit();
    submitted++;
@@ -72,26 +72,19 @@ resume_1:
    }
    if (is_zero((uint64_t*)bs->meta_superblock, bs->dsk.meta_block_size))
    {
-        bs->dsk.check_lengths();
-        {
-            blockstore_meta_header_v3_t *hdr = (blockstore_meta_header_v3_t *)bs->meta_superblock;
-            hdr->zero = 0;
-            hdr->magic = BLOCKSTORE_META_MAGIC_V1;
-            hdr->version = bs->dsk.meta_format;
-            hdr->meta_block_size = bs->dsk.meta_block_size;
-            hdr->data_block_size = bs->dsk.data_block_size;
-            hdr->bitmap_granularity = bs->dsk.bitmap_granularity;
-            if (bs->dsk.meta_format >= BLOCKSTORE_META_FORMAT_V2)
-            {
-                hdr->data_csum_type = bs->dsk.data_csum_type;
-                hdr->csum_block_size = bs->dsk.csum_block_size;
-            }
-            if (bs->dsk.meta_format >= BLOCKSTORE_META_FORMAT_HEAP)
-            {
-                hdr->meta_area_size = bs->dsk.meta_area_size;
-            }
-            hdr->set_crc32c();
-        }
+        assert(bs->dsk.meta_format == BLOCKSTORE_META_FORMAT_HEAP);
+        blockstore_meta_header_v3_t *hdr = (blockstore_meta_header_v3_t *)bs->meta_superblock;
+        hdr->zero = 0;
+        hdr->magic = BLOCKSTORE_META_MAGIC_V1;
+        hdr->version = bs->dsk.meta_format;
+        hdr->meta_block_size = bs->dsk.meta_block_size;
+        hdr->data_block_size = bs->dsk.data_block_size;
+        hdr->bitmap_granularity = bs->dsk.bitmap_granularity;
+        hdr->completed_lsn = 0;
+        hdr->data_csum_type = bs->dsk.data_csum_type;
+        hdr->csum_block_size = bs->dsk.csum_block_size;
+        hdr->meta_area_size = bs->dsk.meta_area_size;
+        hdr->set_crc32c();
        if (bs->readonly)
        {
            printf("Skipping metadata initialization because blockstore is readonly\n");
@@ -99,21 +92,8 @@ resume_1:
        else
        {
            printf("Initializing metadata area\n");
-            GET_SQE();
-            last_read_offset = 0;
-            data->iov = (struct iovec){ bs->meta_superblock, (size_t)bs->dsk.meta_block_size };
-            data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
-            io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset);
-            bs->ringloop->submit();
-            submitted++;
-        resume_2:
-            if (submitted > 0)
-            {
-                wait_state = 2;
-                return 1;
-            }
-            zero_on_init = true;
        }
+        zero_on_init = true;
    }
    else
    {
@@ -141,12 +121,12 @@ resume_1:
            hdr->bitmap_granularity != bs->dsk.bitmap_granularity ||
            hdr->data_csum_type != bs->dsk.data_csum_type ||
            hdr->csum_block_size != bs->dsk.csum_block_size ||
-            hdr->meta_area_size > bs->dsk.meta_area_size)
+            hdr->meta_area_size != bs->dsk.meta_area_size)
        {
            printf(
                "Configuration stored in metadata superblock"
                " (meta_block_size=%u, data_block_size=%u, bitmap_granularity=%u, data_csum_type=%u, csum_block_size=%u, meta_area_size=%ju)"
-                " differs from OSD configuration (%u/%u/%u, %u/%u, %ju).\n",
+                " differs from OSD configuration (%ju/%ju/%u, %u/%u, %ju).\n",
                hdr->meta_block_size, hdr->data_block_size, hdr->bitmap_granularity,
                hdr->data_csum_type, hdr->csum_block_size, hdr->meta_area_size,
                bs->dsk.meta_block_size, bs->dsk.data_block_size, bs->dsk.bitmap_granularity,
@@ -154,17 +134,17 @@ resume_1:
            );
            exit(1);
        }
-        bs->dsk.meta_area_size = hdr->meta_area_size;
-        if (bs->dsk.meta_format != hdr->version)
+        uint32_t csum = hdr->header_csum;
+        hdr->header_csum = 0;
+        if (crc32c(0, hdr, sizeof(*hdr)) != csum)
        {
-            bs->dsk.meta_format = hdr->version;
-            bs->dsk.calc_lengths();
+            printf("Metadata header is corrupt (checksum mismatch).\n");
+            exit(1);
        }
-        bs->dsk.check_lengths();
+        hdr->header_csum = csum;
    }
-    bs->init();
    bs->heap->start_load(((blockstore_meta_header_v3_t *)bs->meta_superblock)->completed_lsn);
-    if (bs->dsk.inmemory_journal)
+    if (bs->dsk.inmemory_journal && !zero_on_init)
    {
        // Read buffer area
        printf("Reading buffered data\n");
@@ -176,7 +156,7 @@ resume_1:
                bs->buffer_area + md_offset,
                (size_t)(bs->dsk.journal_len - md_offset < bs->metadata_buf_size ? bs->dsk.journal_len - md_offset : bs->metadata_buf_size),
            };
-            data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
+            data->callback = [this](ring_data_t *data) { handle_event(data, -1, "read buffer area"); };
            io_uring_prep_readv(sqe, bs->dsk.journal_fd, &data->iov, 1, bs->dsk.journal_offset + md_offset);
            md_offset += data->iov.iov_len;
            submitted++;
@@ -195,7 +175,7 @@ resume_3:
    next_offset = md_offset;
    // Read the rest of the metadata
 resume_4:
-    if (next_offset < bs->dsk.meta_area_size && submitted == 0)
+    if (next_offset < bs->dsk.meta_area_size && submitted == 0 && (!zero_on_init || !bs->readonly))
    {
        // Submit one read
        for (int i = 0; i < 2; i++)
@@ -212,12 +192,15 @@ resume_4:
                GET_SQE();
                assert(bufs[i].size <= 0x7fffffff);
                data->iov = { bufs[i].buf, (size_t)bufs[i].size };
-                data->callback = [this, i](ring_data_t *data) { handle_event(data, i); };
                if (!zero_on_init)
+                {
+                    data->callback = [this, i](ring_data_t *data) { handle_event(data, i, "read metadata"); };
                    io_uring_prep_readv(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bufs[i].offset);
+                }
                else
                {
                    // Fill metadata with empty block pattern
+                    data->callback = [this, i](ring_data_t *data) { handle_event(data, i, "clear metadata"); };
                    memset(bufs[i].buf, 0, bufs[i].size);
                    for (uint64_t o = 0; o < bufs[i].size; o += bs->dsk.meta_block_size)
                        bs->heap->fill_block_empty_space(bufs[i].buf + o, 0);
@@ -233,11 +216,14 @@ resume_4:
        if (bufs[i].state == INIT_META_READ_DONE)
        {
            // Handle result
-            uint64_t loaded = 0;
-            int r = bs->heap->load_blocks(bufs[i].offset-bs->dsk.meta_block_size, bufs[i].size, bufs[i].buf, false, loaded);
-            if (r != 0)
-                exit(1);
-            entries_loaded += loaded;
+            if (!zero_on_init)
+            {
+                uint64_t loaded = 0;
+                int r = bs->heap->load_blocks(bufs[i].offset-bs->dsk.meta_block_size, bufs[i].size, bufs[i].buf, bs->skip_corrupted_meta_entries, loaded);
+                if (r != 0)
+                    exit(1);
+                entries_loaded += loaded;
+            }
            bufs[i].state = 0;
            bs->ringloop->wakeup();
        }
@@ -247,24 +233,9 @@ resume_4:
        wait_state = 4;
        return 1;
    }
-    // metadata read finished
-    printf("Metadata entries loaded: %ju, used blocks: %ju / %ju\n", entries_loaded, bs->heap->get_data_used_space() / bs->dsk.data_block_size, bs->dsk.block_count);
-    if (zero_on_init && !bs->dsk.disable_meta_fsync)
-    {
-        GET_SQE();
-        io_uring_prep_fsync(sqe, bs->dsk.meta_fd, IORING_FSYNC_DATASYNC);
-        last_read_offset = 0;
-        data->iov = { 0 };
-        data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
-        submitted++;
-        bs->ringloop->submit();
-    resume_5:
-        if (submitted > 0)
-        {
-            wait_state = 5;
-            return 1;
-        }
-    }
+    // metadata read/clear finished
+    bs->heap->finish_load();
+    printf("Metadata entries loaded: %ju, rechecking unfinished writes and garbage entries\n", entries_loaded);
    // asynchronous recheck
 resume_6:
    wait_state = 6;
@@ -278,7 +249,7 @@ resume_6:
        }
        GET_SQE();
        data->iov = (iovec){ buf, len };
-        data->callback = [this, offset, cb](ring_data_t *data)
+        data->callback = [offset, cb](ring_data_t *data)
        {
            if (data->res < 0)
            {
@@ -293,7 +264,7 @@ resume_6:
    }, bs->meta_write_recheck_parallelism);
    return 1;
 resume_7:
-    if (bs->heap->finish_load() != 0)
+    if (bs->heap->finish_recheck() != 0)
    {
        exit(1);
    }
@@ -301,6 +272,11 @@ resume_7:
    if (bs->readonly)
    {
        recheck_mod.clear();
+        printf("Actual metadata entries: %ju\n", bs->heap->get_live_entries());
+    }
+    else
+    {
+        printf("Actual metadata entries: %ju, clearing garbage in %zu metadata blocks\n", bs->heap->get_live_entries(), recheck_mod.size());
    }
    for (i = 0; i < recheck_mod.size(); i++)
    {
@@ -314,7 +290,7 @@ resume_8:
        uint32_t block_num = recheck_mod[i];
        uint64_t block_offset = bs->dsk.meta_offset + (uint64_t)(block_num+1) * bs->dsk.meta_block_size;
        data = ((ring_data_t*)sqe->user_data);
-        uint8_t *buf = (uint8_t*)malloc_or_die(bs->dsk.meta_block_size);
+        uint8_t *buf = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, bs->dsk.meta_block_size);
        bs->heap->get_meta_block(block_num, buf);
        data->iov = { buf, bs->dsk.meta_block_size };
        data->callback = [this, buf, block_offset](ring_data_t *data)
@@ -340,5 +316,47 @@ resume_9:
    }
    free(metadata_buffer);
    metadata_buffer = NULL;
+do_fsync:
+    if (!bs->dsk.disable_meta_fsync && !bs->readonly)
+    {
+        GET_SQE();
+        io_uring_prep_fsync(sqe, bs->dsk.meta_fd, IORING_FSYNC_DATASYNC);
+        last_read_offset = 0;
+        data->iov = { 0 };
+        data->callback = [this](ring_data_t *data) { handle_event(data, -1, "fsync metadata"); };
+        submitted++;
+        bs->ringloop->submit();
+    resume_5:
+        if (submitted > 0)
+        {
+            wait_state = 5;
+            return 1;
+        }
+    }
+    if (zero_on_init && !header_written && !bs->readonly)
+    {
+        GET_SQE();
+        header_written = true;
+        last_read_offset = 0;
+        data->iov = (struct iovec){ bs->meta_superblock, (size_t)bs->dsk.meta_block_size };
+        data->callback = [this](ring_data_t *data) { handle_event(data, -1, "write metadata header"); };
+        io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset);
+        bs->ringloop->submit();
+        submitted++;
+    resume_2:
+        if (submitted > 0)
+        {
+            wait_state = 2;
+            return 1;
+        }
+        if (!bs->dsk.disable_meta_fsync)
+        {
+            goto do_fsync;
+        }
+    }
+    printf("Loading finished. Data used: %ju / %ju bytes (%s / %s)\n",
+        bs->heap->get_data_used_space(), bs->dsk.block_count * bs->dsk.data_block_size,
+        format_size(bs->heap->get_data_used_space()).c_str(),
+        format_size(bs->dsk.block_count * bs->dsk.data_block_size).c_str());
    return 0;
 }
@@ -17,6 +17,7 @@ class blockstore_init_meta
    int wait_state = 0;
    int wait_count = 0;
    bool zero_on_init = false;
+    bool header_written = false;
    void *metadata_buffer = NULL;
    blockstore_init_meta_buf bufs[2] = {};
    int submitted = 0;
@@ -29,7 +30,7 @@ class blockstore_init_meta
    std::vector<uint32_t> recheck_mod;
    int i = 0, j = 0;
    bool handle_meta_block(uint8_t *buf, uint64_t count, uint64_t done_cnt);
-    void handle_event(ring_data_t *data, int buf_num);
+    void handle_event(ring_data_t *data, int buf_num, const char *op);
 public:
    blockstore_init_meta(blockstore_impl_t *bs);
    int loop();
@@ -0,0 +1,113 @@
+// Copyright (c) Vitaliy Filippov, 2019+
+// License: VNPL-1.1 (see README.md for details)
+
+#include "blockstore_mock.h"
+
+blockstore_mock_t::blockstore_mock_t(const blockstore_config_t & config)
+{
+}
+
+void blockstore_mock_t::parse_config(blockstore_config_t & config)
+{
+}
+
+void* blockstore_mock_t::reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit)
+{
+    return NULL;
+}
+
+bool blockstore_mock_t::reshard_continue(void *reshard_state, uint64_t chunk_limit)
+{
+    return true;
+}
+
+void blockstore_mock_t::loop()
+{
+}
+
+bool blockstore_mock_t::is_started()
+{
+    return true;
+}
+
+bool blockstore_mock_t::is_stalled()
+{
+    return false;
+}
+
+bool blockstore_mock_t::is_safe_to_stop()
+{
+    return true;
+}
+
+void blockstore_mock_t::enqueue_op(blockstore_op_t *op)
+{
+}
+
+int blockstore_mock_t::read_bitmap(object_id oid, uint64_t target_version, void *bitmap, uint64_t *result_version)
+{
+    return -EIO;
+}
+
+const std::map<uint64_t, uint64_t> & blockstore_mock_t::get_inode_space_stats()
+{
+    return inode_space;
+}
+
+void blockstore_mock_t::set_no_inode_stats(const std::vector<uint64_t> & pool_ids)
+{
+}
+
+void blockstore_mock_t::dump_diagnostics()
+{
+}
+
+std::string blockstore_mock_t::get_op_diag(blockstore_op_t *op)
+{
+    return "";
+}
+
+uint32_t blockstore_mock_t::get_block_size()
+{
+    return block_size;
+}
+
+uint64_t blockstore_mock_t::get_block_count()
+{
+    return block_count;
+}
+
+uint64_t blockstore_mock_t::get_free_block_count()
+{
+    return block_count;
+}
+
+uint64_t blockstore_mock_t::get_journal_size()
+{
+    return 32*1024*1024;
+}
+
+uint32_t blockstore_mock_t::get_bitmap_granularity()
+{
+    return bitmap_granularity;
+}
+
+uint64_t blockstore_mock_t::get_live_entries()
+{
+    return 0;
+}
+
+uint64_t blockstore_mock_t::get_live_memory()
+{
+    return 0;
+}
+
+uint64_t blockstore_mock_t::get_garbage_entries()
+{
+    return 0;
+}
+
+uint64_t blockstore_mock_t::get_garbage_memory()
+{
+    return 0;
+}
@@ -0,0 +1,39 @@
+// Copyright (c) Vitaliy Filippov, 2019+
+// License: VNPL-1.1 (see README.md for details)
+
+#pragma once
+
+#include "blockstore.h"
+
+class blockstore_mock_t: public blockstore_i
+{
+public:
+    uint32_t block_size = 128*1024;
+    uint32_t bitmap_granularity = 4096;
+    uint64_t block_count = 100*1024*8;
+    std::map<uint64_t, uint64_t> inode_space;
+
+    blockstore_mock_t(const blockstore_config_t & config);
+    void parse_config(blockstore_config_t & config) override;
+    void* reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit) override;
+    bool reshard_continue(void *reshard_state, uint64_t chunk_limit) override;
+    void loop() override;
+    bool is_started() override;
+    bool is_stalled() override;
+    bool is_safe_to_stop() override;
+    void enqueue_op(blockstore_op_t *op) override;
+    int read_bitmap(object_id oid, uint64_t target_version, void *bitmap, uint64_t *result_version = NULL) override;
+    const std::map<uint64_t, uint64_t> & get_inode_space_stats() override;
+    void set_no_inode_stats(const std::vector<uint64_t> & pool_ids) override;
+    void dump_diagnostics() override;
+    std::string get_op_diag(blockstore_op_t *op) override;
+    uint32_t get_block_size() override;
+    uint64_t get_block_count() override;
+    uint64_t get_free_block_count() override;
+    uint64_t get_journal_size() override;
+    uint32_t get_bitmap_granularity() override;
+    uint64_t get_live_entries() override;
+    uint64_t get_live_memory() override;
+    uint64_t get_garbage_entries() override;
+    uint64_t get_garbage_memory() override;
+};
@@ -28,6 +28,7 @@ void blockstore_impl_t::parse_config(blockstore_config_t & config, bool init)
    throttle_target_parallelism = strtoull(config["throttle_target_parallelism"].c_str(), NULL, 10);
    throttle_threshold_us = strtoull(config["throttle_threshold_us"].c_str(), NULL, 10);
    perfect_csum_update = config["perfect_csum_update"] == "true" || config["perfect_csum_update"] == "1" || config["perfect_csum_update"] == "yes";
+    skip_corrupted_meta_entries = config["skip_corrupted_meta_entries"] == "true" || config["skip_corrupted_meta_entries"] == "1" || config["skip_corrupted_meta_entries"] == "yes";
    if (config["autosync_writes"] != "")
    {
        autosync_writes = strtoull(config["autosync_writes"].c_str(), NULL, 10);
@@ -22,7 +22,7 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *op)
    uint64_t result_version = 0;
    bool found = false;
    uint32_t skip_csum = 0;
-    uint32_t blk_start = 0, blk_end = 0;
+    uint32_t blk_start = op->offset, blk_end = op->offset+op->len;
    bool need_skip = dsk.csum_block_size > dsk.bitmap_granularity && !perfect_csum_update;
    if (need_skip)
    {
@@ -32,12 +32,28 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *op)
        if (blk_end % dsk.csum_block_size)
            blk_end += dsk.csum_block_size - (blk_end % dsk.csum_block_size);
    }
+    bool need_wait = false;
    heap->iterate_with_stable(obj, obj->lsn, [&](heap_entry_t *wr, bool stable)
    {
        if (wr->type() == BS_HEAP_DELETE)
        {
            return false;
        }
+        if (!heap->is_lsn_completed(wr->lsn))
+        {
+            if (wr->type() == BS_HEAP_BIG_INTENT && wr->big_intent().offset < blk_end && wr->big_intent().offset+wr->big_intent().len > blk_start ||
+                wr->type() == BS_HEAP_INTENT_WRITE && wr->small().offset < blk_end && wr->small().offset+wr->small().len > blk_start)
+            {
+                // Wait until intent write is completed
+                need_wait = true;
+                return false;
+            }
+            else if (wr->type() == BS_HEAP_SMALL_WRITE && wr->small().offset < blk_end && wr->small().offset+wr->small().len > blk_start)
+            {
+                // Skip entry and read the previous one
+                return true;
+            }
+        }
        if (op->version >= wr->version && !found)
        {
            found = true;
@@ -47,12 +63,6 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *op)
                memcpy(op->bitmap, wr->get_ext_bitmap(heap), dsk.clean_entry_bitmap_size);
            }
        }
-        if (need_skip && wr->lsn < heap->get_completed_lsn() &&
-            (wr->type() == BS_HEAP_BIG_INTENT && wr->big_intent().offset < blk_end && wr->big_intent().offset+wr->big_intent().len > blk_start ||
-            wr->type() == BS_HEAP_INTENT_WRITE && wr->small().offset < blk_end && wr->small().offset+wr->small().len > blk_start))
-        {
-            skip_csum = COPY_BUF_SKIP_CSUM;
-        }
        if (op->version >= wr->version)
        {
            fulfilled += prepare_read(PRIV(op)->read_vec, obj, wr, op->offset, op->offset+op->len,
@@ -65,13 +75,23 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *op)
                return false;
            }
        }
-        if (need_skip && (wr->type() == BS_HEAP_SMALL_WRITE || wr->type() == BS_HEAP_INTENT_WRITE) &&
+        if (need_skip && wr->type() == BS_HEAP_SMALL_WRITE &&
            wr->small().offset < blk_end && wr->small().offset+wr->small().len > blk_start)
        {
+            // Small write may mutate big write checksums during flush
            skip_csum = COPY_BUF_SKIP_CSUM;
        }
        return true;
    });
+    if (need_wait)
+    {
+undo_wait:
+        // Need to wait. undo added requests, unlock lsn
+        heap->unlock_entry(op->oid);
+        free_read_buffers(rv);
+        rv.clear();
+        return 0;
+    }
    if (!found)
    {
        // May happen if there are entries but all of them are > requested version
@@ -84,11 +104,7 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *op)
    assert(fulfilled == op->len);
    if (!fulfill_read(op))
    {
-        // Need to wait. undo added requests, unlock lsn
-        heap->unlock_entry(op->oid);
-        free_read_buffers(rv);
-        rv.clear();
-        return 0;
+        goto undo_wait;
    }
    op->version = result_version;
    if (!PRIV(op)->pending_ops)
@@ -446,6 +462,10 @@ int blockstore_impl_t::read_bitmap(object_id oid, uint64_t target_version, void
        {
            if (target_version >= wr->version)
            {
+                if (wr->type() == BS_HEAP_DELETE)
+                {
+                    return false;
+                }
                found = true;
                if (result_version)
                {
@@ -16,6 +16,7 @@ int blockstore_impl_t::dequeue_stable(blockstore_op_t *op)
    else if (priv->op_state == 5) goto resume_5;
    assert(!priv->op_state);
    op->retval = 0;
+    PRIV(op)->lsn = 0;
    priv->modified_block = priv->modified_block2 = UINT32_MAX;
    for (priv->stab_pos = 0; priv->stab_pos < op->len; priv->stab_pos++)
    {
@@ -27,6 +28,7 @@ int blockstore_impl_t::dequeue_stable(blockstore_op_t *op)
                FINISH_OP(op);
                return 2;
            }
+            priv->modified_block2 = UINT32_MAX;
            int res = op->opcode == BS_OP_STABLE
                ? heap->add_commit(obj, v[priv->stab_pos].version, &priv->modified_block2)
                : heap->add_rollback(obj, v[priv->stab_pos].version, &priv->modified_block2);
@@ -36,6 +38,12 @@ int blockstore_impl_t::dequeue_stable(blockstore_op_t *op)
                FINISH_OP(op);
                return 2;
            }
+            if (res == ENOENT)
+            {
+                op->retval = -ENOENT;
+                FINISH_OP(op);
+                return 2;
+            }
            if (res == ENOSPC)
            {
                if (!heap->get_to_compact_count())
@@ -45,11 +53,6 @@ int blockstore_impl_t::dequeue_stable(blockstore_op_t *op)
                    FINISH_OP(op);
                    return 2;
                }
-                if (priv->modified_block2 != UINT32_MAX)
-                {
-                    priv->stab_pos--;
-                    goto resume_1;
-                }
                priv->wait_for = WAIT_COMPACTION;
                priv->wait_detail = heap->get_compacted_count();
                flusher->request_trim();
@@ -57,9 +60,9 @@ int blockstore_impl_t::dequeue_stable(blockstore_op_t *op)
            }
            assert(res == 0);
        }
+resume_1:
        if (priv->modified_block != UINT32_MAX && priv->modified_block2 != priv->modified_block)
        {
-resume_1:
            BS_SUBMIT_CHECK_SQES(1);
            prepare_meta_block_write(priv->modified_block);
 resume_2:
@@ -9,6 +9,7 @@ int blockstore_impl_t::continue_sync(blockstore_op_t *op)
    if (!PRIV(op)->op_state)
    {
        op->retval = 0;
+        PRIV(op)->lsn = 0;
    }
    int res = do_sync(op, 0);
    if (res == 2)
@@ -28,9 +29,12 @@ bool blockstore_impl_t::has_unsynced()

 bool blockstore_impl_t::submit_fsyncs(int & wait_count)
 {
-    int n = (unsynced_meta_write_count > 0 && !dsk.disable_meta_fsync) +
-        (unsynced_buffer_write_count > 0 && !dsk.disable_journal_fsync && dsk.journal_fd != dsk.meta_fd) +
-        (unsynced_data_write_count > 0 && !dsk.disable_data_fsync && dsk.data_fd != dsk.meta_fd && dsk.data_fd != dsk.journal_fd);
+    int n = (unsynced_meta_write_count > 0 && !dsk.disable_meta_fsync ? 1 : 0) +
+        (unsynced_buffer_write_count > 0 && !dsk.disable_journal_fsync &&
+            (!unsynced_meta_write_count || dsk.journal_fd != dsk.meta_fd) ? 1 : 0) +
+        (unsynced_data_write_count > 0 && !dsk.disable_data_fsync &&
+            (!unsynced_meta_write_count || dsk.data_fd != dsk.meta_fd) &&
+            (!unsynced_buffer_write_count || dsk.data_fd != dsk.journal_fd) ? 1 : 0);
    if (ringloop->space_left() < n)
    {
        return false;
@@ -59,7 +63,8 @@ bool blockstore_impl_t::submit_fsyncs(int & wait_count)
        data->callback = cb;
        wait_count++;
    }
-    if (unsynced_buffer_write_count > 0 && !dsk.disable_journal_fsync && dsk.meta_fd != dsk.journal_fd)
+    if (unsynced_buffer_write_count > 0 && !dsk.disable_journal_fsync &&
+        (!unsynced_meta_write_count || dsk.journal_fd != dsk.meta_fd))
    {
        // fsync buffer
        io_uring_sqe *sqe = get_sqe();
@@ -70,7 +75,9 @@ bool blockstore_impl_t::submit_fsyncs(int & wait_count)
        data->callback = cb;
        wait_count++;
    }
-    if (unsynced_data_write_count > 0 && !dsk.disable_data_fsync && dsk.data_fd != dsk.meta_fd && dsk.data_fd != dsk.journal_fd)
+    if (unsynced_data_write_count > 0 && !dsk.disable_data_fsync &&
+        (!unsynced_meta_write_count || dsk.data_fd != dsk.meta_fd) &&
+        (!unsynced_buffer_write_count || dsk.data_fd != dsk.journal_fd))
    {
        // fsync data
        io_uring_sqe *sqe = get_sqe();
@@ -104,9 +111,11 @@ int blockstore_impl_t::do_sync(blockstore_op_t *op, int base_state)
        unsynced_data_write_count = unsynced_buffer_write_count = unsynced_meta_write_count = 0;
        return 2;
    }
-    PRIV(op)->modified_block = heap->get_completed_lsn();
+    assert(!PRIV(op)->lsn);
+    PRIV(op)->lsn = heap->get_completed_lsn();
    if (!submit_fsyncs(PRIV(op)->pending_ops))
    {
+        PRIV(op)->lsn = 0;
        PRIV(op)->wait_detail = 1;
        PRIV(op)->wait_for = WAIT_SQE;
        return 0;
@@ -118,6 +127,6 @@ resume_1:
        return 1;
    }
 resume_2:
-    heap->mark_lsn_fsynced(PRIV(op)->modified_block);
+    heap->mark_lsn_fsynced(PRIV(op)->lsn);
    return 2;
 }
@@ -22,21 +22,24 @@ void blockstore_impl_t::prepare_meta_block_write(uint32_t modified_block)
    ring_data_t *data = ((ring_data_t*)sqe->user_data);
    uint8_t *buf = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, dsk.meta_block_size);
    data->iov = (struct iovec){ buf, (size_t)dsk.meta_block_size };
-    data->callback = [this, modified_block, buf](ring_data_t *data)
+    data->callback = [this, modified_block](ring_data_t *data)
    {
-        free(buf);
        live = true;
        if (data->res != data->iov.iov_len)
        {
            // FIXME: our state becomes corrupted after a write error. maybe do something better than just die
            disk_error_abort("data write", data->res, data->iov.iov_len);
        }
-        modified_blocks.erase(modified_block);
+        auto it = modified_blocks.find(modified_block);
+        assert(it != modified_blocks.end());
+        free(it->second.buf);
+        modified_blocks.erase(it);
        heap->complete_block_write(modified_block);
        ringloop->wakeup();
    };
+    assert(((uint64_t)modified_block+2)*dsk.meta_block_size <= dsk.meta_area_size);
    io_uring_prep_writev(
-        sqe, dsk.meta_fd, &data->iov, 1, dsk.meta_offset + (modified_block+1)*dsk.meta_block_size
+        sqe, dsk.meta_fd, &data->iov, 1, dsk.meta_offset + ((uint64_t)modified_block+1)*dsk.meta_block_size
    );
    unsynced_meta_write_count++;
    pending_modified_blocks.push_back(modified_block);
@@ -175,14 +178,18 @@ enospc:
        ring_data_t *data = ((ring_data_t*)sqe->user_data);
        data->iov = (struct iovec){ op->buf, op->len };
        data->callback = [this, op](ring_data_t *data) { handle_write_event(data, op); };
+        assert(loc+op->offset+op->len <= dsk.block_count*dsk.data_block_size);
        io_uring_prep_writev(sqe, dsk.data_fd, &data->iov, 1, dsk.data_offset + loc + op->offset);
+        if (!dsk.disable_data_fsync)
+        {
+            // use PRIV->lsn for fsync_data_id
+            PRIV(op)->lsn = ++data_fsync_next;
+            data_fsyncs.push_back(false);
+        }
        PRIV(op)->pending_ops++;
        write_iodepth++;
        if (PRIV(op)->write_type == BS_HEAP_BIG_WRITE)
-        {
            PRIV(op)->op_state = 1;
-            inflight_big++;
-        }
        else
            PRIV(op)->op_state = 3;
    }
@@ -249,13 +256,12 @@ enospc:
            goto enospc;
        assert(res == 0);
        PRIV(op)->lsn = obj->lsn;
-        if (op->len)
-            heap->use_buffer_area(op->oid.inode, loc, op->len);
        prepare_meta_block_write(PRIV(op)->modified_block);
        PRIV(op)->pending_ops++;
        if (op->len > 0)
        {
            // Prepare buffered data write
+            heap->use_buffer_area(op->oid.inode, loc, op->len);
            if (dsk.inmemory_journal)
            {
                memcpy((uint8_t*)buffer_area + loc, op->buf, op->len);
@@ -263,6 +269,7 @@ enospc:
            BS_SUBMIT_GET_SQE(sqe2, data2);
            data2->iov = (struct iovec){ op->buf, op->len };
            data2->callback = [this, op](ring_data_t *data) { handle_write_event(data, op); };
+            assert(loc+op->len <= dsk.journal_len);
            io_uring_prep_writev(sqe2, dsk.journal_fd, &data2->iov, 1, dsk.journal_offset + loc);
            PRIV(op)->pending_ops++;
        }
@@ -293,8 +300,6 @@ again:
        goto resume_10;
    else if (op_state == 11)
        goto resume_11;
-    else if (op_state == 12)
-        goto resume_12;
    else
    {
        // In progress
@@ -313,41 +318,48 @@ again:
 resume_2:
    // We must fsync all big writes to avoid complex write workflows
    // It's OK for all HDDs and for server SSDs, but slightly worse for desktop SSDs
-    inflight_big--;
    if (!dsk.disable_data_fsync)
    {
-        // fsync data in a batch
-resume_11:
-        if (inflight_big > 0)
+        // Mark our data write as completed and advance data_fsync_cur
+        data_fsyncs[PRIV(op)->lsn - data_fsync_cur - 1] = true;
+        while (data_fsyncs.size() > 0 && data_fsyncs.front())
+        {
+            data_fsyncs.pop_front();
+            data_fsync_cur++;
+        }
+        PRIV(op)->op_state = 11;
+        // Then wait for all other data writes currently in progress to do less fsync calls
+        // I.e. to fsync data in batches
+        PRIV(op)->lsn = data_fsync_cur + data_fsyncs.size();
+resume_11:
+        if (data_fsync_cur < PRIV(op)->lsn)
        {
-            PRIV(op)->op_state = 11;
            return 1;
        }
-        if (fsyncing_data)
+        if (PRIV(op)->lsn > data_fsync_sent)
        {
-resume_12:
-            if (fsyncing_data)
+            BS_SUBMIT_GET_SQE(sqe, data);
+            io_uring_prep_fsync(sqe, dsk.data_fd, IORING_FSYNC_DATASYNC);
+            data->iov = { 0 };
+            data->callback = [this, op, fs = data_fsync_cur](ring_data_t *data)
            {
-                PRIV(op)->op_state = 12;
-                return 1;
-            }
-            goto resume_4;
+                if (fs > data_fsync_done)
+                {
+                    data_fsync_done = fs;
+                    ringloop->wakeup();
+                }
+            };
+            data_fsync_sent = data_fsync_cur;
        }
-        fsyncing_data = true;
-        BS_SUBMIT_GET_SQE(sqe, data);
-        io_uring_prep_fsync(sqe, dsk.data_fd, IORING_FSYNC_DATASYNC);
-        data->iov = { 0 };
-        data->callback = [this, op](ring_data_t *data)
+        if (PRIV(op)->lsn > data_fsync_done)
        {
-            fsyncing_data = false;
-            handle_write_event(data, op);
-        };
-        PRIV(op)->pending_ops++;
-        PRIV(op)->op_state = 3;
-        return 1;
+            return 1;
+        }
+        PRIV(op)->lsn = 0;
    }
 resume_4:
    {
+        BS_SUBMIT_CHECK_SQES(1);
        auto obj = heap->read_entry(op->oid);
        int res = 0;
        if (PRIV(op)->write_type == _REDIRECT_INTENT)
@@ -404,11 +416,12 @@ resume_6:
        if (ref_us > exec_us + throttle_threshold_us)
        {
            // Pause reply
+            PRIV(op)->pending_ops++;
            PRIV(op)->op_state = 7;
            // Remember that the timer can in theory be called right here
            tfd->set_timer_us(ref_us-exec_us, false, [this, op](int timer_id)
            {
-                PRIV(op)->op_state = 8;
+                PRIV(op)->pending_ops--;
                ringloop->wakeup();
            });
            return 1;
@@ -450,6 +463,7 @@ resume_10:
    BS_SUBMIT_GET_SQE(sqe, data);
    data->iov = (struct iovec){ op->buf, op->len };
    data->callback = [this, op](ring_data_t *data) { handle_write_event(data, op); };
+    assert(PRIV(op)->location + op->offset <= dsk.block_count*dsk.data_block_size);
    io_uring_prep_writev(sqe, dsk.data_fd, &data->iov, 1, dsk.data_offset + PRIV(op)->location + op->offset);
    if (dsk.use_atomic_flag)
        sqe->rw_flags = RWF_ATOMIC;
@@ -12,7 +12,7 @@ multilist_alloc_t::multilist_alloc_t(uint32_t count, uint32_t maxn):
    count(count), maxn(maxn)
 {
    // not-so-memory-efficient: 16 MB memory per 1 GB buffer space, but buffer spaces are small, so OK
-    assert(count > 1 && count < 0x80000000);
+    assert(count > 1 && count < 0x80000000 && count >= maxn);
    sizes.resize(count);
    nexts.resize(count); // nexts[i] = 0 -> area is used; nexts[i] = 1 -> no next; nexts[i] >= 2 -> next item
    prevs.resize(count);
@@ -171,7 +171,7 @@ void multilist_alloc_t::print()
    printf("\n");
 }

-void multilist_alloc_t::use(uint32_t pos, uint32_t size)
+bool multilist_alloc_t::use(uint32_t pos, uint32_t size)
 {
    assert(pos+size <= count && size > 0);
    if (sizes[pos] <= 0)
@@ -182,7 +182,8 @@ void multilist_alloc_t::use(uint32_t pos, uint32_t size)
        else
            while (start > 0 && !sizes[start])
                start--;
-        assert(sizes[start] >= size);
+        if (sizes[start] < size+(pos-start))
+            return false;
        use_full(start);
        uint32_t full = sizes[start];
        sizes[pos-1] = -pos+start;
@@ -199,7 +200,8 @@ void multilist_alloc_t::use(uint32_t pos, uint32_t size)
    }
    else
    {
-        assert(sizes[pos] >= size);
+        if (sizes[pos] < size)
+            return false;
        use_full(pos);
        if (sizes[pos] > size)
        {
@@ -214,12 +216,13 @@ void multilist_alloc_t::use(uint32_t pos, uint32_t size)
 #ifdef MULTILIST_TRACE
    print();
 #endif
+    return true;
 }

 void multilist_alloc_t::use_full(uint32_t pos)
 {
    uint32_t prevsize = sizes[pos];
-    assert(prevsize);
+    assert(prevsize > 0);
    assert(nexts[pos]);
    uint32_t pi = (prevsize < maxn ? prevsize : maxn)-1;
    if (heads[pi] == pos+1)
@@ -17,7 +17,7 @@ struct multilist_alloc_t
    bool is_free(uint32_t pos);
    uint32_t find(uint32_t size);
    void use_full(uint32_t pos);
-    void use(uint32_t pos, uint32_t size);
+    bool use(uint32_t pos, uint32_t size);
    void do_free(uint32_t pos);
    void free(uint32_t pos);
    void verify();
@@ -141,7 +141,7 @@ struct __attribute__((__packed__)) journal_entry
 inline uint32_t je_crc32(journal_entry *je)
 {
    // 0x48674bc7 = crc32(4 zero bytes)
-    return crc32c(0x48674bc7, ((uint8_t*)je)+4, je->size-4);
+    return je->size < 4 ? 0 : crc32c(0x48674bc7, ((uint8_t*)je)+4, je->size-4);
 }

 // "VITAstor"
@@ -71,6 +71,11 @@ bool journal_flusher_t::is_active()
    return active_flushers > 0 || dequeuing;
 }

+size_t journal_flusher_t::get_queue_size()
+{
+    return flush_queue.size();
+}
+
 void journal_flusher_t::loop()
 {
    target_flusher_count = bs->write_iodepth*2;
@@ -384,6 +389,7 @@ stop_flusher:
        wait_state = 0;
        return true;
    }
+    copy_count = 0;
    try_trim = true;
    cur.oid = flusher->flush_queue.front();
    cur.version = flusher->flush_versions[cur.oid];
@@ -511,6 +517,31 @@ resume_2:
            {
                uo_it->second.was_changed = true;
            }
+            if (!bs->journal.inmemory)
+            {
+                // Verify journaled data checksums (but not COALESCED)
+                for (it = v.begin(); it != v.end(); it++)
+                {
+                    if (it->copy_flags == COPY_BUF_JOURNAL)
+                    {
+                        iovec iov = { .iov_base = it->buf, .iov_len = it->len };
+                        bs->verify_journal_checksums(
+                            it->csum_buf, it->offset, &iov, 1,
+                            [&](uint32_t bad_block, uint32_t calc_csum, uint32_t stored_csum)
+                            {
+                                printf(
+                                    "Checksum mismatch in object %jx:%jx v%ju in journal at 0x%jx, checksum block #%u: got %08x, expected %08x\n",
+                                    cur.oid.inode, cur.oid.stripe, cur.version, it->disk_offset,
+                                    bad_block / bs->dsk.csum_block_size, calc_csum, stored_csum
+                                );
+                                bad_block += it->offset;
+                                assert(!(bad_block % bs->dsk.csum_block_size) && bad_block < bs->dsk.data_block_size);
+                                mangle_csum_blocks.insert(bad_block);
+                            }
+                        );
+                    }
+                }
+            }
        }
        // Submit data writes
        for (it = v.begin(); it != v.end(); it++)
@@ -520,6 +551,7 @@ resume_2:
                await_sqe(15);
                data->iov = (struct iovec){ it->buf, (size_t)it->len };
                data->callback = simple_callback_w;
+                assert(clean_loc+it->offset+it->len <= bs->dsk.block_count*bs->dsk.data_block_size);
                io_uring_prep_writev(
                    sqe, bs->dsk.data_fd, &data->iov, 1, bs->dsk.data_offset + clean_loc + it->offset
                );
@@ -633,6 +665,7 @@ resume_2:
        }
        // All done
        flusher->active_flushers--;
+        copy_count = 0; // used by is_mutated()...
        wait_state = 0;
        goto resume_0;
    }
@@ -749,6 +782,7 @@ bool journal_flusher_co::write_meta_block(flusher_meta_write_t & meta_block, int
    await_sqe(0);
    data->iov = (struct iovec){ meta_block.buf, (size_t)bs->dsk.meta_block_size };
    data->callback = simple_callback_w;
+    assert(bs->dsk.meta_block_size + meta_block.sector + bs->dsk.meta_block_size <= bs->dsk.meta_area_size);
    io_uring_prep_writev(
        sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bs->dsk.meta_block_size + meta_block.sector
    );
@@ -813,35 +847,21 @@ bool journal_flusher_co::clear_incomplete_csum_block_bits(int wait_base)
                bs->verify_padded_checksums(new_clean_bitmap, new_clean_bitmap + 2*bs->dsk.clean_entry_bitmap_size,
                    v[i].offset, &iov, 1, [&](uint32_t bad_block, uint32_t calc_csum, uint32_t stored_csum)
                {
-                    printf("Checksum mismatch in object %jx:%jx v%ju in data area at offset 0x%jx+0x%x: got %08x, expected %08x\n",
+                    printf("Checksum mismatch in object %jx:%jx v%ju in data area at offset 0x%jx+0x%x during flush: got %08x, expected %08x\n",
                        cur.oid.inode, cur.oid.stripe, old_clean_ver, old_clean_loc, bad_block, calc_csum, stored_csum);
-                    for (uint32_t j = 0; j < bs->dsk.csum_block_size; j += bs->dsk.bitmap_granularity)
-                    {
-                        // Simplest method of mangling: flip one byte in every sector
-                        ((uint8_t*)v[i].buf)[j+bad_block-v[i].offset] ^= 0xff;
-                    }
+                    assert(!(bad_block % bs->dsk.csum_block_size) && bad_block < bs->dsk.data_block_size);
+                    mangle_csum_blocks.insert(bad_block);
                });
            }
            else
            {
                bs->verify_journal_checksums(v[i].csum_buf, v[i].offset, &iov, 1, [&](uint32_t bad_block, uint32_t calc_csum, uint32_t stored_csum)
                {
-                    printf("Checksum mismatch in object %jx:%jx v%ju in journal at offset 0x%jx+0x%x (block offset 0x%jx): got %08x, expected %08x\n",
+                    printf("Checksum mismatch in object %jx:%jx v%ju in journal at offset 0x%jx+0x%x (block offset 0x%jx) during flush: got %08x, expected %08x\n",
                        cur.oid.inode, cur.oid.stripe, old_clean_ver,
                        v[i].disk_offset, bad_block, v[i].offset, calc_csum, stored_csum);
-                    bad_block += (v[i].offset/bs->dsk.csum_block_size) * bs->dsk.csum_block_size;
-                    uint32_t bad_block_end = bad_block + bs->dsk.csum_block_size + (v[i].offset/bs->dsk.csum_block_size) * bs->dsk.csum_block_size;
-                    if (bad_block < v[i].offset)
-                        bad_block = v[i].offset;
-                    if (bad_block_end > v[i].offset+v[i].len)
-                        bad_block_end = v[i].offset+v[i].len;
-                    bad_block -= v[i].offset;
-                    bad_block_end -= v[i].offset;
-                    for (uint32_t j = bad_block; j < bad_block_end; j += bs->dsk.bitmap_granularity)
-                    {
-                        // Simplest method of mangling: flip one byte in every sector
-                        ((uint8_t*)v[i].buf)[j] ^= 0xff;
-                    }
+                    assert(!(bad_block % bs->dsk.csum_block_size) && bad_block < bs->dsk.data_block_size);
+                    mangle_csum_blocks.insert(bad_block);
                });
            }
        }
@@ -950,6 +970,11 @@ void journal_flusher_co::calc_block_checksums(uint32_t *new_data_csums, bool ski
    }
    // `v` should contain aligned items, possibly split into pieces
    assert(!block_done);
+    for (uint32_t mangle_block: mangle_csum_blocks)
+    {
+        // Flip 1 bit
+        new_data_csums[mangle_block / bs->dsk.csum_block_size] ^= 1;
+    }
 }

 void journal_flusher_co::scan_dirty()
@@ -1086,7 +1111,8 @@ void journal_flusher_co::scan_dirty()
            last--;
        read_to_fill_incomplete = bs->fill_partial_checksum_blocks(
            v, fulfilled, bmp_ptr, NULL, false, NULL, v[0].offset/bs->dsk.csum_block_size * bs->dsk.csum_block_size,
-            ((v[last].offset+v[last].len-1) / bs->dsk.csum_block_size + 1) * bs->dsk.csum_block_size
+            ((v[last].offset+v[last].len-1) / bs->dsk.csum_block_size + 1) * bs->dsk.csum_block_size,
+            0, bs->dsk.data_block_size
        );
    }
    else if (fill_incomplete && clean_init_bitmap)
@@ -1116,6 +1142,7 @@ bool journal_flusher_co::read_dirty(int wait_base)
    if (wait_state == wait_base)        goto resume_0;
    else if (wait_state == wait_base+1) goto resume_1;
    wait_count = wait_journal_count = 0;
+    mangle_csum_blocks.clear();
    if (bs->journal.inmemory && !read_to_fill_incomplete)
    {
        // Happy path: nothing to read :)
@@ -1347,7 +1374,7 @@ bool journal_flusher_co::fsync_batch(bool fsync_meta, int wait_base)
        cur_sync->ready_count++;
        flusher->syncing_flushers++;
    resume_1:
-        if (!cur_sync->state)
+        if (cur_sync->state == 0)
        {
            if (flusher->syncing_flushers >= flusher->active_flushers || !flusher->flush_queue.size())
            {
@@ -1375,6 +1402,12 @@ bool journal_flusher_co::fsync_batch(bool fsync_meta, int wait_base)
                return false;
            }
        }
+        else if (cur_sync->state == 1)
+        {
+            // Wait for fsync completion
+            wait_state = wait_base+1;
+            return false;
+        }
        flusher->syncing_flushers--;
        cur_sync->ready_count--;
        if (cur_sync->ready_count == 0)
@@ -66,6 +66,7 @@ class journal_flusher_co
    uint64_t clean_bitmap_offset, clean_bitmap_len;
    uint8_t *clean_init_dyn_ptr;
    uint8_t *new_clean_bitmap;
+    std::unordered_set<uint32_t> mangle_csum_blocks;

    uint64_t new_trim_pos;

@@ -123,6 +124,7 @@ public:
    void loop();
    bool is_trim_wanted() { return trim_wanted; }
    bool is_active();
+    size_t get_queue_size();
    void mark_trim_possible();
    void request_trim();
    void release_trim();
@@ -6,11 +6,12 @@

 namespace v1 {

-blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_i *ringloop, timerfd_manager_t *tfd)
+blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_i *ringloop, timerfd_manager_t *tfd, bool mock_mode)
 {
    assert(sizeof(blockstore_op_private_t) <= BS_OP_PRIVATE_DATA_SIZE);
    this->tfd = tfd;
    this->ringloop = ringloop;
+    dsk.mock_mode = mock_mode;
    ring_consumer.loop = [this]() { loop(); };
    ringloop->register_consumer(&ring_consumer);
    initialized = 0;
@@ -35,6 +36,11 @@ blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_i *

 blockstore_impl_t::~blockstore_impl_t()
 {
+    for (auto& obj: dirty_db)
+    {
+        if (obj.second.dyn_data)
+            free(obj.second.dyn_data);
+    }
    delete data_alloc;
    delete flusher;
    if (zero_object)
@@ -407,32 +413,77 @@ blockstore_clean_db_t& blockstore_impl_t::clean_db_shard(object_id oid)
    return clean_db_shards[(pool_id << (64-POOL_ID_BITS)) | pg_num];
 }

-void blockstore_impl_t::reshard_clean_db(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size)
+struct bs_reshard_state_t
 {
-    uint64_t pool_id = (uint64_t)pool;
+    int state = 0;
+    uint64_t pool_id = 0;
+    uint32_t pg_count = 0;
+    uint32_t pg_stripe_size = 0;
+    uint64_t chunk_size = 0;
+    std::map<pool_pg_id_t, blockstore_clean_db_t> old_shards;
    std::map<pool_pg_id_t, blockstore_clean_db_t> new_shards;
-    auto sh_it = clean_db_shards.lower_bound((pool_id << (64-POOL_ID_BITS)));
-    while (sh_it != clean_db_shards.end() &&
-        (sh_it->first >> (64-POOL_ID_BITS)) == pool_id)
+    std::map<pool_pg_id_t, blockstore_clean_db_t>::iterator sh_it;
+    blockstore_clean_db_t::iterator obj_it;
+};
+
+void* blockstore_impl_t::reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit)
+{
+    auto & settings = clean_db_settings[pool];
+    if (settings.pg_count == pg_count && settings.pg_stripe_size == pg_stripe_size)
    {
-        for (auto & pair: sh_it->second)
-        {
-            // like map_to_pg()
-            uint64_t pg_num = (pair.first.stripe / pg_stripe_size) % pg_count + 1;
-            uint64_t shard_id = (pool_id << (64-POOL_ID_BITS)) | pg_num;
-            new_shards[shard_id][pair.first] = pair.second;
-        }
+        return NULL;
+    }
+    bs_reshard_state_t *st = new bs_reshard_state_t;
+    st->state = 0;
+    st->pool_id = pool;
+    st->pg_count = pg_count;
+    st->pg_stripe_size = pg_stripe_size;
+    auto sh_it = clean_db_shards.lower_bound((st->pool_id << (64-POOL_ID_BITS)));
+    while (sh_it != clean_db_shards.end() &&
+        (sh_it->first >> (64-POOL_ID_BITS)) == st->pool_id)
+    {
+        st->old_shards[sh_it->first] = std::move(sh_it->second);
        clean_db_shards.erase(sh_it++);
    }
-    for (sh_it = new_shards.begin(); sh_it != new_shards.end(); sh_it++)
+    bool finished = reshard_continue(st, chunk_limit);
+    return finished ? NULL : st;
+}
+
+bool blockstore_impl_t::reshard_continue(void *reshard_state, uint64_t chunk_limit)
+{
+    bs_reshard_state_t *st = (bs_reshard_state_t*)reshard_state;
+    uint64_t chunk_size = 0;
+    if (st->state == 1)
+        goto resume_1;
+    for (st->sh_it = st->old_shards.begin(); st->sh_it != st->old_shards.end(); )
+    {
+        for (st->obj_it = st->sh_it->second.begin(); st->obj_it != st->sh_it->second.end(); st->obj_it++)
+        {
+            if (chunk_limit > 0 && chunk_size >= chunk_limit)
+            {
+                st->state = 1;
+                return false;
+            }
+resume_1:
+            // like map_to_pg()
+            uint64_t pg_num = (st->obj_it->first.stripe / st->pg_stripe_size) % st->pg_count + 1;
+            uint64_t shard_id = (st->pool_id << (64-POOL_ID_BITS)) | pg_num;
+            st->new_shards[shard_id][st->obj_it->first] = st->obj_it->second;
+            chunk_size++;
+        }
+        st->old_shards.erase(st->sh_it++);
+    }
+    for (auto sh_it = st->new_shards.begin(); sh_it != st->new_shards.end(); sh_it++)
    {
        auto & to = clean_db_shards[sh_it->first];
        to.swap(sh_it->second);
    }
-    clean_db_settings[pool_id] = (pool_shard_settings_t){
-        .pg_count = pg_count,
-        .pg_stripe_size = pg_stripe_size,
+    clean_db_settings[st->pool_id] = (pool_shard_settings_t){
+        .pg_count = st->pg_count,
+        .pg_stripe_size = st->pg_stripe_size,
    };
+    delete st;
+    return true;
 }

 void blockstore_impl_t::process_list(blockstore_op_t *op)
@@ -465,7 +516,10 @@ void blockstore_impl_t::process_list(blockstore_op_t *op)
                sh_it->second.pg_count != pg_count ||
                sh_it->second.pg_stripe_size != pg_stripe_size)
            {
-                reshard_clean_db(pool_id, pg_count, pg_stripe_size);
+                // Sharding mismatch
+                op->retval = -EAGAIN;
+                FINISH_OP(op);
+                return;
            }
            first_shard = last_shard = ((uint64_t)pool_id << (64-POOL_ID_BITS)) | list_pg;
        }
@@ -807,4 +861,29 @@ std::string blockstore_impl_t::get_op_diag(blockstore_op_t *op)
    return std::string(buf);
 }

+uint64_t blockstore_impl_t::get_live_entries()
+{
+    return used_blocks;
+}
+
+uint64_t blockstore_impl_t::get_live_memory()
+{
+    uint64_t used = 0;
+    for (auto & kv: clean_db_shards)
+    {
+        used += kv.second.size() * sizeof(blockstore_clean_db_t::value_type);
+    }
+    return used;
+}
+
+uint64_t blockstore_impl_t::get_garbage_entries()
+{
+    return dirty_db.size();
+}
+
+uint64_t blockstore_impl_t::get_garbage_memory()
+{
+    return (sizeof(obj_ver_id) + sizeof(dirty_entry) + 32) * dirty_db.size();
+}
+
 } // namespace v1
@@ -30,6 +30,8 @@

 //#define BLOCKSTORE_DEBUG

+struct bs_test_t;
+
 namespace v1 {

 #include "journal.h"
@@ -96,7 +98,7 @@ struct blockstore_op_private_t
    int op_state;

    // Read
-    uint64_t clean_block_used;
+    uint64_t clean_loc_used;
    std::vector<copy_buffer_t> read_vec;

    // Sync, write
@@ -122,6 +124,7 @@ typedef uint64_t pool_pg_id_t;

 class blockstore_impl_t: public blockstore_i
 {
+    friend struct ::bs_test_t;
    blockstore_disk_t dsk;

    /******* OPTIONS *******/
@@ -202,7 +205,6 @@ class blockstore_impl_t: public blockstore_i
    uint8_t* get_clean_entry_bitmap(uint64_t block_loc, int offset);

    blockstore_clean_db_t& clean_db_shard(object_id oid);
-    void reshard_clean_db(pool_id_t pool_id, uint32_t pg_count, uint32_t pg_stripe_size);
    void recalc_inode_space_stats(uint64_t pool_id, bool per_inode);

    // Journaling
@@ -221,6 +223,7 @@ class blockstore_impl_t: public blockstore_i

    // Read
    int dequeue_read(blockstore_op_t *read_op);
+    void release_clean(blockstore_op_t *op);
    void find_holes(std::vector<copy_buffer_t> & read_vec, uint32_t item_start, uint32_t item_end,
        std::function<int(int, bool, uint32_t, uint32_t)> callback);
    int fulfill_read(blockstore_op_t *read_op,
@@ -231,7 +234,8 @@ class blockstore_impl_t: public blockstore_i
        uint8_t *clean_entry_bitmap, int *dyn_data,
        uint32_t item_start, uint32_t item_end, uint64_t clean_loc, uint64_t clean_ver);
    int fill_partial_checksum_blocks(std::vector<copy_buffer_t> & rv, uint64_t & fulfilled,
-        uint8_t *clean_entry_bitmap, int *dyn_data, bool from_journal, uint8_t *read_buf, uint64_t read_offset, uint64_t read_end);
+        uint8_t *clean_entry_bitmap, int *dyn_data, bool from_journal, uint8_t *read_buf,
+        uint32_t read_offset, uint32_t read_end, uint32_t item_start, uint32_t item_end);
    int pad_journal_read(std::vector<copy_buffer_t> & rv, copy_buffer_t & cp,
        uint64_t dirty_offset, uint64_t dirty_end, uint64_t dirty_loc, uint8_t *csum_ptr, int *dyn_data,
        uint64_t offset, uint64_t submit_len, uint64_t & blk_begin, uint64_t & blk_end, uint8_t* & blk_buf);
@@ -282,12 +286,16 @@ class blockstore_impl_t: public blockstore_i

 public:

-    blockstore_impl_t(blockstore_config_t & config, ring_loop_i *ringloop, timerfd_manager_t *tfd);
+    blockstore_impl_t(blockstore_config_t & config, ring_loop_i *ringloop, timerfd_manager_t *tfd, bool mock_mode = false);
    ~blockstore_impl_t();

    void parse_config(blockstore_config_t & config);
    void parse_config(blockstore_config_t & config, bool init);

+    // Reshard database for a pool
+    void* reshard_start(pool_id_t pool, uint32_t pg_count, uint32_t pg_stripe_size, uint64_t chunk_limit);
+    bool reshard_continue(void *reshard_state, uint64_t chunk_limit);
+
    // Event loop
    void loop();

@@ -329,6 +337,10 @@ public:
    inline uint64_t get_free_block_count() { return dsk.block_count - used_blocks; }
    inline uint32_t get_bitmap_granularity() { return dsk.disk_alignment; }
    inline uint64_t get_journal_size() { return dsk.journal_len; }
+    uint64_t get_live_entries();
+    uint64_t get_live_memory();
+    uint64_t get_garbage_entries();
+    uint64_t get_garbage_memory();
 };

 } // namespace v1
@@ -1,6 +1,7 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)

+#include "str_util.h"
 #include "impl.h"
 #include "internal.h"

@@ -30,14 +31,15 @@ blockstore_init_meta::blockstore_init_meta(blockstore_impl_t *bs)
    this->bs = bs;
 }

-void blockstore_init_meta::handle_event(ring_data_t *data, int buf_num)
+void blockstore_init_meta::handle_event(ring_data_t *data, int buf_num, const char *op)
 {
-    if (data->res < 0)
+    if (data->res != data->iov.iov_len)
    {
-        throw std::runtime_error(
-            std::string("read metadata failed at offset ") + std::to_string(buf_num >= 0 ? bufs[buf_num].offset : last_read_offset) +
-            std::string(": ") + strerror(-data->res)
-        );
+        throw std::runtime_error(strprintf(
+            "%s failed at offset %ju: got %s (code %d), but expected %zu",
+            op, (buf_num >= 0 ? bufs[buf_num].offset : last_read_offset), strerror(-data->res),
+            data->res, data->iov.iov_len
+        ));
    }
    if (buf_num >= 0)
    {
@@ -65,10 +67,11 @@ int blockstore_init_meta::loop()
    if (!metadata_buffer)
        throw std::runtime_error("Failed to allocate metadata read buffer");
    // Read superblock
+    hdr = (blockstore_meta_header_v2_t *)memalign_or_die(MEM_ALIGNMENT, bs->dsk.meta_block_size);
    GET_SQE();
    last_read_offset = 0;
-    data->iov = { metadata_buffer, (size_t)bs->dsk.meta_block_size };
-    data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
+    data->iov = { hdr, (size_t)bs->dsk.meta_block_size };
+    data->callback = [this](ring_data_t *data) { handle_event(data, -1, "read metadata header"); };
    io_uring_prep_readv(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset);
    bs->ringloop->submit();
    submitted++;
@@ -78,24 +81,8 @@ resume_1:
        wait_state = 1;
        return 1;
    }
-    if (iszero((uint64_t*)metadata_buffer, bs->dsk.meta_block_size / sizeof(uint64_t)))
+    if (iszero((uint64_t*)hdr, bs->dsk.meta_block_size / sizeof(uint64_t)))
    {
-        {
-            blockstore_meta_header_v2_t *hdr = (blockstore_meta_header_v2_t *)metadata_buffer;
-            hdr->zero = 0;
-            hdr->magic = BLOCKSTORE_META_MAGIC_V1;
-            hdr->version = bs->dsk.meta_format;
-            hdr->meta_block_size = bs->dsk.meta_block_size;
-            hdr->data_block_size = bs->dsk.data_block_size;
-            hdr->bitmap_granularity = bs->dsk.bitmap_granularity;
-            if (bs->dsk.meta_format >= BLOCKSTORE_META_FORMAT_V2)
-            {
-                hdr->data_csum_type = bs->dsk.data_csum_type;
-                hdr->csum_block_size = bs->dsk.csum_block_size;
-                hdr->header_csum = 0;
-                hdr->header_csum = crc32c(0, hdr, sizeof(*hdr));
-            }
-        }
        if (bs->readonly)
        {
            printf("Skipping metadata initialization because blockstore is readonly\n");
@@ -103,25 +90,11 @@ resume_1:
        else
        {
            printf("Initializing metadata area\n");
-            GET_SQE();
-            last_read_offset = 0;
-            data->iov = (struct iovec){ metadata_buffer, (size_t)bs->dsk.meta_block_size };
-            data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
-            io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset);
-            bs->ringloop->submit();
-            submitted++;
-        resume_3:
-            if (submitted > 0)
-            {
-                wait_state = 3;
-                return 1;
-            }
-            zero_on_init = true;
        }
+        zero_on_init = true;
    }
    else
    {
-        blockstore_meta_header_v2_t *hdr = (blockstore_meta_header_v2_t *)metadata_buffer;
        if (hdr->zero != 0 || hdr->magic != BLOCKSTORE_META_MAGIC_V1 || hdr->version < BLOCKSTORE_META_FORMAT_V1)
        {
            printf(
@@ -189,7 +162,7 @@ resume_1:
            printf(
                "Configuration stored in metadata superblock"
                " (meta_block_size=%u, data_block_size=%u, bitmap_granularity=%u, data_csum_type=%u, csum_block_size=%u)"
-                " differs from OSD configuration (%u/%u/%u, %u/%u).\n",
+                " differs from OSD configuration (%ju/%ju/%u, %u/%u).\n",
                hdr->meta_block_size, hdr->data_block_size, hdr->bitmap_granularity,
                hdr->data_csum_type, hdr->csum_block_size,
                bs->dsk.meta_block_size, bs->dsk.data_block_size, bs->dsk.bitmap_granularity,
@@ -223,12 +196,15 @@ resume_2:
                GET_SQE();
                assert(bufs[i].size <= 0x7fffffff);
                data->iov = { bufs[i].buf, (size_t)bufs[i].size };
-                data->callback = [this, i](ring_data_t *data) { handle_event(data, i); };
                if (!zero_on_init)
+                {
+                    data->callback = [this, i](ring_data_t *data) { handle_event(data, i, "read metadata"); };
                    io_uring_prep_readv(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bufs[i].offset);
+                }
                else
                {
                    // Fill metadata with zeroes
+                    data->callback = [this, i](ring_data_t *data) { handle_event(data, i, "clear metadata"); };
                    memset(data->iov.iov_base, 0, data->iov.iov_len);
                    io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bufs[i].offset);
                }
@@ -256,7 +232,7 @@ resume_2:
                GET_SQE();
                assert(bufs[i].size <= 0x7fffffff);
                data->iov = { bufs[i].buf, (size_t)bufs[i].size };
-                data->callback = [this, i](ring_data_t *data) { handle_event(data, i); };
+                data->callback = [this, i](ring_data_t *data) { handle_event(data, i, "write metadata"); };
                io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bufs[i].offset);
                bs->ringloop->submit();
                bufs[i].state = INIT_META_WRITING;
@@ -285,7 +261,7 @@ resume_2:
            GET_SQE();
            last_read_offset = (1+next_offset)*bs->dsk.meta_block_size;
            data->iov = { metadata_buffer, (size_t)bs->dsk.meta_block_size };
-            data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
+            data->callback = [this](ring_data_t *data) { handle_event(data, -1, "read metadata"); };
            io_uring_prep_readv(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + (1+next_offset)*bs->dsk.meta_block_size);
            bs->ringloop->submit();
            submitted++;
@@ -302,7 +278,7 @@ resume_5:
            }
            GET_SQE();
            data->iov = { metadata_buffer, (size_t)bs->dsk.meta_block_size };
-            data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
+            data->callback = [this](ring_data_t *data) { handle_event(data, -1, "write metadata"); };
            io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + (1+next_offset)*bs->dsk.meta_block_size);
            bs->ringloop->submit();
            submitted++;
@@ -317,27 +293,64 @@ resume_6:
    }
    // metadata read finished
    printf("Metadata entries loaded: %ju, free blocks: %ju / %ju\n", entries_loaded, bs->data_alloc->get_free_count(), bs->dsk.block_count);
+    if (zero_on_init && !bs->readonly)
+    {
+do_fsync:
+        if (!bs->disable_meta_fsync)
+        {
+            GET_SQE();
+            io_uring_prep_fsync(sqe, bs->dsk.meta_fd, IORING_FSYNC_DATASYNC);
+            last_read_offset = 0;
+            data->iov = { 0 };
+            data->callback = [this](ring_data_t *data) { handle_event(data, -1, "fsync metadata"); };
+            submitted++;
+            bs->ringloop->submit();
+resume_4:
+            if (submitted > 0)
+            {
+                wait_state = 4;
+                return 1;
+            }
+        }
+        if (!header_written)
+        {
+            GET_SQE();
+            hdr->zero = 0;
+            hdr->magic = BLOCKSTORE_META_MAGIC_V1;
+            hdr->version = bs->dsk.meta_format;
+            hdr->meta_block_size = bs->dsk.meta_block_size;
+            hdr->data_block_size = bs->dsk.data_block_size;
+            hdr->bitmap_granularity = bs->dsk.bitmap_granularity;
+            if (bs->dsk.meta_format >= BLOCKSTORE_META_FORMAT_V2)
+            {
+                hdr->data_csum_type = bs->dsk.data_csum_type;
+                hdr->csum_block_size = bs->dsk.csum_block_size;
+                hdr->header_csum = 0;
+                hdr->header_csum = crc32c(0, hdr, sizeof(*hdr));
+            }
+            header_written = true;
+            last_read_offset = 0;
+            data->iov = (struct iovec){ hdr, (size_t)bs->dsk.meta_block_size };
+            data->callback = [this](ring_data_t *data) { handle_event(data, -1, "write metadata header"); };
+            io_uring_prep_writev(sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset);
+            bs->ringloop->submit();
+            submitted++;
+resume_3:
+            if (submitted > 0)
+            {
+                wait_state = 3;
+                return 1;
+            }
+            goto do_fsync;
+        }
+    }
    if (!bs->inmemory_meta)
    {
        free(metadata_buffer);
        metadata_buffer = NULL;
    }
-    if (zero_on_init && !bs->disable_meta_fsync)
-    {
-        GET_SQE();
-        io_uring_prep_fsync(sqe, bs->dsk.meta_fd, IORING_FSYNC_DATASYNC);
-        last_read_offset = 0;
-        data->iov = { 0 };
-        data->callback = [this](ring_data_t *data) { handle_event(data, -1); };
-        submitted++;
-        bs->ringloop->submit();
-    resume_4:
-        if (submitted > 0)
-        {
-            wait_state = 4;
-            return 1;
-        }
-    }
+    free(hdr);
+    hdr = NULL;
    return 0;
 }

@@ -345,6 +358,8 @@ bool blockstore_init_meta::handle_meta_block(uint8_t *buf, uint64_t entries_per_
 {
    bool updated = false;
    uint64_t max_i = entries_per_block;
+    if (done_cnt > bs->dsk.block_count)
+        return false;
    if (max_i > bs->dsk.block_count-done_cnt)
        max_i = bs->dsk.block_count-done_cnt;
    for (uint64_t i = 0; i < max_i; i++)
@@ -455,21 +470,21 @@ blockstore_init_journal::blockstore_init_journal(blockstore_impl_t *bs)
    };
 }

-void blockstore_init_journal::handle_event(ring_data_t *data1)
+void blockstore_init_journal::handle_event(ring_data_t *data)
 {
-    if (data1->res <= 0)
+    if (data->res != data->iov.iov_len)
    {
-        throw std::runtime_error(
-            std::string("read journal failed at offset ") + std::to_string(journal_pos) +
-            std::string(": ") + strerror(-data1->res)
-        );
+        throw std::runtime_error(strprintf(
+            "read journal failed at offset %ju: got %s (code %d), but expected %zu",
+            journal_pos, strerror(-data->res), data->res, data->iov.iov_len
+        ));
    }
    done.push_back({
        .buf = submitted_buf,
        .pos = journal_pos,
-        .len = (uint64_t)data1->res,
+        .len = (uint64_t)data->res,
    });
-    journal_pos += data1->res;
+    journal_pos += data->res;
    if (journal_pos >= bs->journal.len)
    {
        // Continue from the beginning
@@ -16,7 +16,9 @@ class blockstore_init_meta
    blockstore_impl_t *bs;
    int wait_state = 0;
    bool zero_on_init = false;
+    bool header_written = false;
    void *metadata_buffer = NULL;
+    blockstore_meta_header_v2_t *hdr = NULL;
    blockstore_init_meta_buf bufs[2] = {};
    int submitted = 0;
    struct io_uring_sqe *sqe;
@@ -29,7 +31,7 @@ class blockstore_init_meta
    int i = 0, j = 0;
    std::vector<uint64_t> entries_to_zero;
    bool handle_meta_block(uint8_t *buf, uint64_t count, uint64_t done_cnt);
-    void handle_event(ring_data_t *data, int buf_num);
+    void handle_event(ring_data_t *data, int buf_num, const char *op);
 public:
    blockstore_init_meta(blockstore_impl_t *bs);
    int loop();
@@ -193,6 +193,7 @@ void blockstore_impl_t::prepare_journal_sector_write(int cur_sector, blockstore_
            (size_t)journal.block_size
        };
        data->callback = [this, flush_id = journal.submit_id](ring_data_t *data) { handle_journal_write(data, flush_id); };
+        assert(journal.sector_info[cur_sector].offset+journal.block_size <= dsk.journal_len);
        io_uring_prep_writev(
            sqe, dsk.journal_fd, &data->iov, 1, journal.offset + journal.sector_info[cur_sector].offset
        );
@@ -101,8 +101,8 @@ int blockstore_impl_t::fulfill_read(blockstore_op_t *read_op,
                    .copy_flags = COPY_BUF_JOURNAL|COPY_BUF_CSUM_FILL,
                    .offset = blk_begin,
                    .len = blk_end-blk_begin,
-                    .csum_buf = (csum + (blk_begin/dsk.csum_block_size -
-                        item_start/dsk.csum_block_size) * (dsk.data_csum_type & 0xFF)),
+                    .csum_buf = (!csum ? NULL : (csum + (blk_begin/dsk.csum_block_size -
+                        item_start/dsk.csum_block_size) * (dsk.data_csum_type & 0xFF))),
                    .dyn_data = dyn_data,
                });
                if (dyn_data)
@@ -134,7 +134,7 @@ int blockstore_impl_t::fulfill_read(blockstore_op_t *read_op,
                // If we don't track it then we may IN THEORY read another object's data:
                // submit read -> remove the object -> flush remove -> overwrite with another object -> finish read
                // Very improbable, but possible
-                PRIV(read_op)->clean_block_used = 1;
+                PRIV(read_op)->clean_loc_used = UINT64_MAX;
            }
            rv.insert(rv.begin() + pos, el);
            fulfilled += el.len;
@@ -167,7 +167,8 @@ uint8_t* blockstore_impl_t::get_clean_entry_bitmap(uint64_t block_loc, int offse
 }

 int blockstore_impl_t::fill_partial_checksum_blocks(std::vector<copy_buffer_t> & rv, uint64_t & fulfilled,
-    uint8_t *clean_entry_bitmap, int *dyn_data, bool from_journal, uint8_t *read_buf, uint64_t read_offset, uint64_t read_end)
+    uint8_t *clean_entry_bitmap, int *dyn_data, bool from_journal, uint8_t *read_buf,
+    uint32_t read_offset, uint32_t read_end, uint32_t item_start, uint32_t item_end)
 {
    if (read_end == read_offset)
        return 0;
@@ -175,10 +176,38 @@ int blockstore_impl_t::fill_partial_checksum_blocks(std::vector<copy_buffer_t> &
    read_buf -= read_offset;
    uint32_t last_block = (read_end-1)/dsk.csum_block_size;
    uint32_t start_block = read_offset/dsk.csum_block_size;
+    uint32_t item_start_block = item_start/dsk.csum_block_size;
    uint32_t end_block = 0;
+    auto zero_range = [&](int pos, bool alloc, uint32_t cur_start, uint32_t cur_end)
+    {
+        if (alloc)
+            return 0;
+        copy_buffer_t el = {
+            .copy_flags = COPY_BUF_ZERO,
+            .offset = cur_start,
+            .len = cur_end-cur_start,
+        };
+        rv.insert(rv.begin() + pos, el);
+        if (read_buf)
+            memset(read_buf + el.offset - read_offset, 0, el.len);
+        fulfilled += el.len;
+        return 1;
+    };
+    if (read_offset < item_start)
+    {
+        // Zero-fill the beginning
+        find_holes(rv, read_offset, item_start, zero_range);
+        read_offset = item_start;
+    }
+    if (read_end > item_end)
+    {
+        // Zero-fill the end
+        find_holes(rv, item_end, read_end, zero_range);
+        read_end = item_end;
+    }
    while (start_block <= last_block)
    {
-        if (read_range_fulfilled(rv, fulfilled, read_buf, clean_entry_bitmap,
+        if (read_range_fulfilled(rv, fulfilled, read_buf, from_journal ? NULL : clean_entry_bitmap,
            start_block*dsk.csum_block_size < read_offset ? read_offset : start_block*dsk.csum_block_size,
            (start_block+1)*dsk.csum_block_size > read_end ? read_end : (start_block+1)*dsk.csum_block_size))
        {
@@ -190,7 +219,7 @@ int blockstore_impl_t::fill_partial_checksum_blocks(std::vector<copy_buffer_t> &
            // Find a sequence of checksum blocks required to be read
            end_block = start_block;
            while ((end_block+1)*dsk.csum_block_size < read_end &&
-                !read_range_fulfilled(rv, fulfilled, read_buf, clean_entry_bitmap,
+                !read_range_fulfilled(rv, fulfilled, read_buf, from_journal ? NULL : clean_entry_bitmap,
                    (end_block+1)*dsk.csum_block_size < read_offset ? read_offset : (end_block+1)*dsk.csum_block_size,
                    (end_block+2)*dsk.csum_block_size > read_end ? read_end : (end_block+2)*dsk.csum_block_size))
            {
@@ -202,8 +231,10 @@ int blockstore_impl_t::fill_partial_checksum_blocks(std::vector<copy_buffer_t> &
                .copy_flags = COPY_BUF_CSUM_FILL | (from_journal ? COPY_BUF_JOURNALED_BIG : 0),
                .offset = start_block*dsk.csum_block_size,
                .len = (end_block-start_block)*dsk.csum_block_size,
-                // save clean_entry_bitmap if we're reading clean data from the journal
-                .csum_buf = from_journal ? clean_entry_bitmap : NULL,
+                // save checksum reference if we're reading clean data from the journal
+                .csum_buf = from_journal
+                    ? clean_entry_bitmap + dsk.clean_entry_bitmap_size + (start_block-item_start_block)*(dsk.data_csum_type & 0xFF)
+                    : NULL,
                .dyn_data = dyn_data,
            });
            if (dyn_data)
@@ -226,6 +257,11 @@ bool blockstore_impl_t::read_range_fulfilled(std::vector<copy_buffer_t> & rv, ui
    {
        if (alloc)
            return 0;
+        if (!clean_entry_bitmap)
+        {
+            all_done = false;
+            return 0;
+        }
        int diff = 0;
        uint32_t bmp_start = cur_start/dsk.bitmap_granularity;
        uint32_t bmp_end = cur_end/dsk.bitmap_granularity;
@@ -323,7 +359,7 @@ bool blockstore_impl_t::read_checksum_block(blockstore_op_t *op, int rv_pos, uin
            {
                iov[n_iov++] = (struct iovec){ (uint8_t*)op->buf+cur_start-op->offset, lim_end-cur_start };
                rv.insert(rv.begin() + pos, (copy_buffer_t){
-                    .copy_flags = COPY_BUF_DATA,
+                    .copy_flags = COPY_BUF_DATA|COPY_BUF_COALESCED,
                    .offset = cur_start,
                    .len = lim_end-cur_start,
                });
@@ -361,10 +397,10 @@ bool blockstore_impl_t::read_checksum_block(blockstore_op_t *op, int rv_pos, uin
        PRIV(op)->pending_ops++;
        io_uring_prep_readv(sqe, submit_fd, iov + n_pos, n_cur, submit_offset + clean_loc + item_start + d_pos);
        data->callback = [this, op](ring_data_t *data) { handle_read_event(data, op); };
-        if (n_pos > 0 || n_pos + IOV_MAX < n_iov)
+        if (n_pos > 0 || n_iov > IOV_MAX)
        {
            uint32_t d_len = 0;
-            for (int i = 0; i < IOV_MAX; i++)
+            for (int i = 0; i < n_cur; i++)
                d_len += iov[n_pos+i].iov_len;
            data->iov.iov_len = d_len;
            d_pos += d_len;
@@ -376,7 +412,7 @@ bool blockstore_impl_t::read_checksum_block(blockstore_op_t *op, int rv_pos, uin
    {
        // Reads running parallel to flushes of the same clean block may read
        // a mixture of old and new data. So we don't verify checksums for such blocks.
-        PRIV(op)->clean_block_used = 1;
+        PRIV(op)->clean_loc_used = UINT64_MAX;
    }
    return true;
 }
@@ -402,7 +438,7 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
    }
    uint64_t fulfilled = 0;
    PRIV(read_op)->pending_ops = 0;
-    PRIV(read_op)->clean_block_used = 0;
+    PRIV(read_op)->clean_loc_used = 0;
    auto & rv = PRIV(read_op)->read_vec;
    uint64_t result_version = 0;
    if (dirty_found)
@@ -515,26 +551,50 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
    return 2;
 undo_read:
    // need to wait. undo added requests, don't dequeue op
-    if (dsk.csum_block_size > dsk.bitmap_granularity)
+    release_clean(read_op);
+    for (auto & vec: rv)
    {
-        for (auto & vec: rv)
+        if ((vec.copy_flags & COPY_BUF_CSUM_FILL) && vec.buf)
        {
-            if ((vec.copy_flags & COPY_BUF_CSUM_FILL) && vec.buf)
-            {
-                free(vec.buf);
-                vec.buf = NULL;
-            }
-            if (vec.dyn_data && --(*vec.dyn_data) == 0) // refcount
-            {
-                free(vec.dyn_data);
-                vec.dyn_data = NULL;
-            }
+            free(vec.buf);
+            vec.buf = NULL;
+        }
+        if (vec.dyn_data && --(*vec.dyn_data) == 0) // refcount
+        {
+            free(vec.dyn_data);
+            vec.dyn_data = NULL;
        }
    }
    rv.clear();
    return 0;
 }

+void blockstore_impl_t::release_clean(blockstore_op_t *op)
+{
+    if (PRIV(op)->clean_loc_used == UINT64_MAX)
+    {
+        PRIV(op)->clean_loc_used = 0;
+    }
+    if (PRIV(op)->clean_loc_used)
+    {
+        // Release clean data block
+        auto uo_it = used_clean_objects.find(PRIV(op)->clean_loc_used - 1);
+        if (uo_it != used_clean_objects.end())
+        {
+            uo_it->second.refs--;
+            if (uo_it->second.refs <= 0)
+            {
+                if (uo_it->second.was_freed)
+                {
+                    data_alloc->set((PRIV(op)->clean_loc_used - 1) / dsk.data_block_size, false);
+                }
+                used_clean_objects.erase(uo_it);
+            }
+        }
+        PRIV(op)->clean_loc_used = 0;
+    }
+}
+
 int blockstore_impl_t::pad_journal_read(std::vector<copy_buffer_t> & rv, copy_buffer_t & cp,
    // FIXME Passing dirty_entry& would be nicer
    uint64_t dirty_offset, uint64_t dirty_end, uint64_t dirty_loc, uint8_t *csum_ptr, int *dyn_data,
@@ -598,11 +658,15 @@ bool blockstore_impl_t::fulfill_clean_read(blockstore_op_t *read_op, uint64_t &
    {
        auto & rv = PRIV(read_op)->read_vec;
        int req = fill_partial_checksum_blocks(rv, fulfilled, clean_entry_bitmap, dyn_data, from_journal,
-            (uint8_t*)read_op->buf, read_op->offset, read_op->offset+read_op->len);
+            (uint8_t*)read_op->buf, read_op->offset, read_op->offset+read_op->len, item_start, item_end);
        if (!inmemory_meta && !from_journal && req > 0)
        {
            // Read checksums from disk
            uint8_t *csum_buf = read_clean_meta_block(read_op, clean_loc, rv.size()-req);
+            if (!csum_buf)
+            {
+                return false;
+            }
            for (int i = req; i > 0; i--)
            {
                rv[rv.size()-i].csum_buf = csum_buf;
@@ -615,13 +679,12 @@ bool blockstore_impl_t::fulfill_clean_read(blockstore_op_t *read_op, uint64_t &
                return false;
            }
        }
-        PRIV(read_op)->clean_block_used = req > 0;
+        PRIV(read_op)->clean_loc_used = req > 0 ? UINT64_MAX : 0;
    }
    else if (from_journal)
    {
        // Don't scan bitmap - journal writes don't have holes (internal bitmap)!
-        uint8_t *csum = !dsk.csum_block_size ? 0 : (clean_entry_bitmap + dsk.clean_entry_bitmap_size +
-            item_start/dsk.csum_block_size*(dsk.data_csum_type & 0xFF));
+        uint8_t *csum = !dsk.csum_block_size ? 0 : (clean_entry_bitmap + dsk.clean_entry_bitmap_size);
        if (!fulfill_read(read_op, fulfilled, item_start, item_end,
            (BS_ST_BIG_WRITE | BS_ST_STABLE), 0, clean_loc + item_start, 0, csum, dyn_data))
        {
@@ -666,6 +729,10 @@ bool blockstore_impl_t::fulfill_clean_read(blockstore_op_t *read_op, uint64_t &
                {
                    // Read checksums from disk
                    csum_buf = read_clean_meta_block(read_op, clean_loc, PRIV(read_op)->read_vec.size());
+                    if (!csum_buf)
+                    {
+                        return false;
+                    }
                    csum_done = true;
                }
                uint8_t *csum = !dsk.csum_block_size ? 0 : (csum_buf + 2*dsk.clean_entry_bitmap_size + bmp_start*(dsk.data_csum_type & 0xFF));
@@ -680,13 +747,13 @@ bool blockstore_impl_t::fulfill_clean_read(blockstore_op_t *read_op, uint64_t &
        }
    }
    // Increment reference counter if clean data is being read from the disk
-    if (PRIV(read_op)->clean_block_used)
+    if (PRIV(read_op)->clean_loc_used == UINT64_MAX)
    {
        auto & uo = used_clean_objects[clean_loc];
        uo.refs++;
        if (dsk.csum_block_size && flusher->is_mutated(clean_loc))
            uo.was_changed = true;
-        PRIV(read_op)->clean_block_used = clean_loc;
+        PRIV(read_op)->clean_loc_used = clean_loc + 1;
    }
    return true;
 }
@@ -726,12 +793,18 @@ bool blockstore_impl_t::verify_padded_checksums(uint8_t *clean_entry_bitmap, uin
        while (pos < iov[i].iov_len)
        {
            uint32_t start = pos;
-            uint8_t bit = (clean_entry_bitmap[bmp_pos >> 3] >> (bmp_pos & 0x7)) & 1;
-            while (pos < iov[i].iov_len && ((clean_entry_bitmap[bmp_pos >> 3] >> (bmp_pos & 0x7)) & 1) == bit)
+            uint8_t bit = 1;
+            if (clean_entry_bitmap)
            {
-                pos += dsk.bitmap_granularity;
-                bmp_pos++;
+                bit = (clean_entry_bitmap[bmp_pos >> 3] >> (bmp_pos & 0x7)) & 1;
+                while (pos < iov[i].iov_len && ((clean_entry_bitmap[bmp_pos >> 3] >> (bmp_pos & 0x7)) & 1) == bit)
+                {
+                    pos += dsk.bitmap_granularity;
+                    bmp_pos++;
+                }
            }
+            else
+                pos = iov[i].iov_len;
            uint32_t len = pos-start;
            auto buf = (uint8_t*)iov[i].iov_base+start;
            while (block_done+len >= dsk.csum_block_size)
@@ -808,7 +881,7 @@ bool blockstore_impl_t::verify_clean_padded_checksums(blockstore_op_t *op, uint6
 {
    uint32_t offset = clean_loc % dsk.data_block_size;
    if (from_journal)
-        return verify_padded_checksums(dyn_data, dyn_data + dsk.clean_entry_bitmap_size, offset, iov, n_iov, bad_block_cb);
+        return verify_padded_checksums(NULL, dyn_data, offset, iov, n_iov, bad_block_cb);
    clean_loc = (clean_loc / dsk.data_block_size) * dsk.data_block_size;
    if (!dyn_data)
    {
@@ -836,7 +909,7 @@ void blockstore_impl_t::handle_read_event(ring_data_t *data, blockstore_op_t *op
            void *meta_block = NULL;
            if (dsk.csum_block_size > dsk.bitmap_granularity)
            {
-                for (int i = rv.size()-1; i >= 0 && (rv[i].copy_flags & COPY_BUF_CSUM_FILL); i--)
+                for (int i = 0; i < rv.size(); i++)
                {
                    if (rv[i].copy_flags & COPY_BUF_META_BLOCK)
                    {
@@ -846,8 +919,41 @@ void blockstore_impl_t::handle_read_event(ring_data_t *data, blockstore_op_t *op
                        rv[i].buf = NULL;
                        continue;
                    }
-                    struct iovec *iov = (struct iovec*)((uint8_t*)rv[i].buf + (rv[i].len & 0xFFFFFFFF));
-                    int n_iov = rv[i].len >> 32;
+                    if (rv[i].copy_flags & COPY_BUF_ZERO)
+                    {
+                        // Zero read
+                        continue;
+                    }
+                    if (rv[i].copy_flags & COPY_BUF_COALESCED)
+                    {
+                        // Sub-block shared with another read. Skip
+                        continue;
+                    }
+                    if ((rv[i].copy_flags & COPY_BUF_JOURNAL) && journal.inmemory)
+                    {
+                        // Do not check journal checksums in-memory
+                        continue;
+                    }
+                    iovec single_iov = {};
+                    iovec *iov = NULL;
+                    int n_iov = 0;
+                    if (rv[i].copy_flags & COPY_BUF_CSUM_FILL)
+                    {
+                        // Padded, buffer list passed using a 'creepy way'
+                        iov = (struct iovec*)((uint8_t*)rv[i].buf + (rv[i].len & 0xFFFFFFFF));
+                        n_iov = rv[i].len >> 32;
+                    }
+                    else
+                    {
+                        // Not padded, buffer is fully within the input buffer
+                        assert(op->buf);
+                        assert(rv[i].csum_buf);
+                        iov = &single_iov;
+                        n_iov = 1;
+                        assert(rv[i].offset >= op->offset);
+                        assert(rv[i].offset + rv[i].len <= op->offset + op->len);
+                        single_iov = { .iov_base = op->buf + rv[i].offset - op->offset, .iov_len = rv[i].len };
+                    }
                    bool ok = true;
                    if (rv[i].copy_flags & COPY_BUF_JOURNAL)
                    {
@@ -945,23 +1051,7 @@ void blockstore_impl_t::handle_read_event(ring_data_t *data, blockstore_op_t *op
                meta_block = NULL;
            }
        }
-        if (PRIV(op)->clean_block_used)
-        {
-            // Release clean data block
-            auto uo_it = used_clean_objects.find(PRIV(op)->clean_block_used);
-            if (uo_it != used_clean_objects.end())
-            {
-                uo_it->second.refs--;
-                if (uo_it->second.refs <= 0)
-                {
-                    if (uo_it->second.was_freed)
-                    {
-                        data_alloc->set(PRIV(op)->clean_block_used, false);
-                    }
-                    used_clean_objects.erase(uo_it);
-                }
-            }
-        }
+        release_clean(op);
        if (!journal.inmemory)
        {
            // Release journal sector usage
@@ -491,7 +491,7 @@ void blockstore_impl_t::mark_stable(obj_ver_id v, bool forget_dirty)
                    if (!exists)
                    {
                        uint64_t space_id = dirty_it->first.oid.inode;
-                        if (no_inode_stats[dirty_it->first.oid.inode >> (64-POOL_ID_BITS)])
+                        if (no_inode_stats.find(dirty_it->first.oid.inode >> (64-POOL_ID_BITS)) != no_inode_stats.end())
                            space_id = space_id & ~(((uint64_t)1 << (64-POOL_ID_BITS)) - 1);
                        inode_space_stats[space_id] += dsk.data_block_size;
                        used_blocks++;
@@ -501,7 +501,7 @@ void blockstore_impl_t::mark_stable(obj_ver_id v, bool forget_dirty)
                else if (IS_DELETE(dirty_it->second.state))
                {
                    uint64_t space_id = dirty_it->first.oid.inode;
-                    if (no_inode_stats[dirty_it->first.oid.inode >> (64-POOL_ID_BITS)])
+                    if (no_inode_stats.find(dirty_it->first.oid.inode >> (64-POOL_ID_BITS)) != no_inode_stats.end())
                        space_id = space_id & ~(((uint64_t)1 << (64-POOL_ID_BITS)) - 1);
                    auto & sp = inode_space_stats[space_id];
                    if (sp > dsk.data_block_size)
@@ -183,7 +183,7 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
        uint32_t end = (op->offset+op->len-1) / dsk.csum_block_size;
        auto fn = state & BS_ST_BIG_WRITE ? crc32c_pad : crc32c_nopad;
        if (start == end)
-            data_csums[0] = fn(0, op->buf, op->len, op->offset - start*dsk.csum_block_size, end*dsk.csum_block_size - (op->offset+op->len));
+            data_csums[0] = fn(0, op->buf, op->len, op->offset - start*dsk.csum_block_size, (end+1)*dsk.csum_block_size - (op->offset+op->len));
        else
        {
            // First block
@@ -368,9 +368,9 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
        }
        data->iov.iov_len = op->len + stripe_offset + stripe_end; // to check it in the callback
        data->callback = [this, op](ring_data_t *data) { handle_write_event(data, op); };
-        io_uring_prep_writev(
-            sqe, dsk.data_fd, PRIV(op)->iov_zerofill, vcnt, dsk.data_offset + (loc * dsk.data_block_size) + op->offset - stripe_offset
-        );
+        const uint64_t write_offset = (loc * dsk.data_block_size) + op->offset - stripe_offset;
+        assert(write_offset+op->len+stripe_offset+stripe_end <= dsk.block_count*dsk.data_block_size);
+        io_uring_prep_writev(sqe, dsk.data_fd, PRIV(op)->iov_zerofill, vcnt, dsk.data_offset + write_offset);
        PRIV(op)->pending_ops = 1;
        if (!(dirty_it->second.state & BS_ST_INSTANT))
        {
@@ -495,9 +495,8 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
                .op = op,
            });
            data2->callback = [this, flush_id = journal.submit_id](ring_data_t *data) { handle_journal_write(data, flush_id); };
-            io_uring_prep_writev(
-                sqe2, dsk.journal_fd, &data2->iov, 1, journal.offset + journal.next_free
-            );
+            assert(journal.next_free+op->len <= dsk.journal_len);
+            io_uring_prep_writev(sqe2, dsk.journal_fd, &data2->iov, 1, journal.offset + journal.next_free);
            PRIV(op)->pending_ops++;
        }
        else
@@ -1,8 +1,24 @@
-cmake_minimum_required(VERSION 2.8.12)
+cmake_minimum_required(VERSION 2.8...3.30)

 project(vitastor)

 # libvitastor_common.a
+add_library(vitastor_common STATIC
+	etcd_state_client.cpp
+	msgr_stop.cpp
+	msgr_op.cpp
+	../../json11/json11.cpp
+	osd_ops.cpp
+	pg_states.cpp
+	../util/allocator.cpp
+	../util/addr_util.cpp
+	../util/timerfd_manager.cpp
+	../util/str_util.cpp
+	../util/json_util.cpp
+)
+target_compile_options(vitastor_common PUBLIC -fPIC)
+
+# libvitastor_net.a
 set(MSGR_RDMA "")
 if (IBVERBS_LIBRARIES)
 	set(MSGR_RDMA "msgr_rdma.cpp")
@@ -11,24 +27,32 @@ set(MSGR_RDMACM "")
 if (RDMACM_LIBRARIES)
 	set(MSGR_RDMACM "msgr_rdmacm.cpp")
 endif (RDMACM_LIBRARIES)
-add_library(vitastor_common STATIC
-	../util/epoll_manager.cpp etcd_state_client.cpp messenger.cpp ../util/addr_util.cpp
-	msgr_stop.cpp msgr_op.cpp msgr_send.cpp msgr_receive.cpp ../util/ringloop.cpp ../../json11/json11.cpp
-	http_client.cpp osd_ops.cpp pg_states.cpp ../util/timerfd_manager.cpp ../util/str_util.cpp ../util/json_util.cpp ${MSGR_RDMA} ${MSGR_RDMACM}
+add_library(vitastor_net STATIC
+	../util/epoll_manager.cpp
+	etcd_state_client_http.cpp
+	messenger.cpp
+	msgr_iothread.cpp
+	msgr_send.cpp
+	msgr_receive.cpp
+	../util/ringloop.cpp
+	http_client.cpp
+	${MSGR_RDMA}
+	${MSGR_RDMACM}
 )
-target_link_libraries(vitastor_common pthread)
-target_compile_options(vitastor_common PUBLIC -fPIC)
+target_link_libraries(vitastor_net pthread vitastor_common)
+target_compile_options(vitastor_net PUBLIC -fPIC)

 # libvitastor_client.so
 add_library(vitastor_client SHARED
 	cluster_client.cpp
+	cluster_client_real.cpp
 	cluster_client_list.cpp
 	cluster_client_wb.cpp
 	vitastor_c.cpp
 )
 set_target_properties(vitastor_client PROPERTIES PUBLIC_HEADER "client/vitastor_c.h")
 target_link_libraries(vitastor_client
-	vitastor_common
+	vitastor_net
 	vitastor_cli
 	${LIBURING_LIBRARIES}
 	${IBVERBS_LIBRARIES}
@@ -52,9 +76,6 @@ if (${WITH_FIO})
 		../util/rw_blocking.cpp
 		../util/addr_util.cpp
 	)
-	target_link_libraries(fio_vitastor_sec
-		tcmalloc_minimal
-	)
 endif (${WITH_FIO})

 # vitastor-nbd
@@ -98,10 +119,13 @@ endif (${WITH_QEMU})
 add_executable(test_cluster_client
 	EXCLUDE_FROM_ALL
 	../test/test_cluster_client.cpp
-	pg_states.cpp osd_ops.cpp cluster_client.cpp cluster_client_list.cpp cluster_client_wb.cpp msgr_op.cpp ../test/mock/messenger.cpp msgr_stop.cpp
-	etcd_state_client.cpp ../util/timerfd_manager.cpp ../util/addr_util.cpp ../util/str_util.cpp ../util/json_util.cpp ../../json11/json11.cpp
+	cluster_client.cpp
+	cluster_client_list.cpp
+	cluster_client_wb.cpp
+	../test/mock/messenger.cpp
+	etcd_state_client_mock.cpp
 )
-target_compile_definitions(test_cluster_client PUBLIC -D__MOCK__)
+target_link_libraries(test_cluster_client vitastor_common ${LIBURING_LIBRARIES})
 target_include_directories(test_cluster_client BEFORE PUBLIC ${CMAKE_SOURCE_DIR}/src/test/mock)
 add_dependencies(build_tests test_cluster_client)
 add_test(NAME test_cluster_client COMMAND test_cluster_client)
@@ -11,7 +11,7 @@
 #define TRY_SEND_CONNECTING 1
 #define TRY_SEND_OK 2

-cluster_client_t::cluster_client_t(ring_loop_t *ringloop, timerfd_manager_t *tfd, json11::Json config)
+cluster_client_t::cluster_client_t(ring_loop_t *ringloop, timerfd_manager_t *tfd, json11::Json config, std::unique_ptr<etcd_state_client_t> st_cli_ptr)
 {
    wb = new writeback_cache_t();

@@ -27,7 +27,7 @@ cluster_client_t::cluster_client_t(ring_loop_t *ringloop, timerfd_manager_t *tfd
    msgr.ringloop = ringloop;
    msgr.repeer_pgs = [this](osd_num_t peer_osd)
    {
-        if (msgr.osd_peer_fds.find(peer_osd) != msgr.osd_peer_fds.end())
+        if (msgr.osd_peers.find(peer_osd) != msgr.osd_peers.end())
        {
            // peer_osd just connected
            continue_ops();
@@ -47,29 +47,29 @@ cluster_client_t::cluster_client_t(ring_loop_t *ringloop, timerfd_manager_t *tfd
    msgr.exec_op = [this](osd_op_t *op)
    {
        // Garbage in
-        fprintf(stderr, "Incoming garbage from peer %d\n", op->peer_fd);
-        msgr.stop_client(op->peer_fd);
+        fprintf(stderr, "Can't handle incoming operation from client %lu\n", op->client_id);
+        msgr.stop_client(op->client_id);
        delete op;
    };
    msgr.parse_config(config);

-    st_cli.tfd = tfd;
-    st_cli.on_load_config_hook = [this](json11::Json::object & cfg) { on_load_config_hook(cfg); };
-    st_cli.on_change_osd_state_hook = [this](uint64_t peer_osd) { on_change_osd_state_hook(peer_osd); };
-    st_cli.on_change_pool_config_hook = [this]() { on_change_pool_config_hook(); };
-    st_cli.on_change_pg_config_hook = [this]() { on_change_pool_config_hook(); };
-    st_cli.on_change_pg_state_hook = [this](pool_id_t pool_id, pg_num_t pg_num, osd_num_t prev_primary) { on_change_pg_state_hook(pool_id, pg_num, prev_primary); };
-    st_cli.on_change_node_placement_hook = [this]() { on_change_node_placement_hook(); };
-    st_cli.on_load_pgs_hook = [this](bool success) { on_load_pgs_hook(success); };
-    st_cli.on_reload_hook = [this]() { st_cli.load_global_config(); };
+    st_cli = std::move(st_cli_ptr);
+    st_cli->on_load_config_hook = [this](json11::Json::object & cfg) { on_load_config_hook(cfg); };
+    st_cli->on_change_osd_state_hook = [this](uint64_t peer_osd) { on_change_osd_state_hook(peer_osd); };
+    st_cli->on_change_pool_config_hook = [this]() { on_change_pool_config_hook(); };
+    st_cli->on_change_pg_config_hook = [this]() { on_change_pool_config_hook(); };
+    st_cli->on_change_pg_state_hook = [this](pool_id_t pool_id, pg_num_t pg_num, osd_num_t prev_primary) { on_change_pg_state_hook(pool_id, pg_num, prev_primary); };
+    st_cli->on_change_node_placement_hook = [this]() { on_change_node_placement_hook(); };
+    st_cli->on_load_pgs_hook = [this](bool success) { on_load_pgs_hook(success); };
+    st_cli->on_reload_hook = [this]() { this->st_cli->load_global_config(); };

-    st_cli.parse_config(config);
-    st_cli.infinite_start = false;
+    st_cli->parse_config(config);
+    st_cli->infinite_start = false;
    if (!config["client_infinite_start"].is_null())
    {
-        st_cli.infinite_start = config["client_infinite_start"].bool_value();
+        st_cli->infinite_start = config["client_infinite_start"].bool_value();
    }
-    st_cli.load_global_config();
+    st_cli->load_global_config();

    scrap_buffer_size = SCRAP_BUFFER_SIZE;
    scrap_buffer = malloc_or_die(scrap_buffer_size);
@@ -156,7 +156,7 @@ void cluster_client_t::continue_raw_ops(osd_num_t peer_osd)
    {
        auto op = it->second;
        op->op_type = OSD_OP_OUT;
-        op->peer_fd = msgr.osd_peer_fds.at(peer_osd);
+        op->client_id = msgr.osd_peers.at(peer_osd)->client_id;
        msgr.outbox_push(op);
        raw_ops.erase(it++);
    }
@@ -469,7 +469,7 @@ void cluster_client_t::on_load_config_hook(json11::Json::object & etcd_global_co
        auto etcd_report_interval = config["etcd_report_interval"].uint64_value();
        if (!etcd_report_interval)
            etcd_report_interval = 5;
-        client_wait_up_timeout = 1+etcd_report_interval+(st_cli.max_etcd_attempts*(2*st_cli.etcd_quick_timeout)+999)/1000;
+        client_wait_up_timeout = 1+etcd_report_interval+(st_cli->max_etcd_attempts*(2*st_cli->etcd_quick_timeout)+999)/1000;
    }
    // log_level
    log_level = config["log_level"].uint64_value();
@@ -482,8 +482,8 @@ void cluster_client_t::on_load_config_hook(json11::Json::object & etcd_global_co
        client_hostname = new_hostname;
    }
    msgr.parse_config(config);
-    st_cli.parse_config(config);
-    st_cli.load_pgs();
+    st_cli->parse_config(config);
+    st_cli->load_pgs();
 }

 osd_num_t cluster_client_t::select_random_osd(const std::vector<osd_num_t> & osds)
@@ -492,7 +492,7 @@ osd_num_t cluster_client_t::select_random_osd(const std::vector<osd_num_t> & osd
    int alive_count = 0;
    for (auto & osd_num: osds)
    {
-        if (!st_cli.peer_states[osd_num].is_null())
+        if (!st_cli->peer_states[osd_num].is_null())
            alive_set[alive_count++] = osd_num;
    }
    if (!alive_count)
@@ -509,7 +509,7 @@ osd_num_t cluster_client_t::select_nearest_osd(const std::vector<osd_num_t> & os
        while (self_tree_metrics.find(cur_id) == self_tree_metrics.end())
        {
            self_tree_metrics[cur_id] = metric++;
-            json11::Json cur_placement = st_cli.node_placement[cur_id];
+            json11::Json cur_placement = st_cli->node_placement[cur_id];
            cur_id = cur_placement["parent"].string_value();
        }
        if (cur_id != "")
@@ -529,7 +529,7 @@ osd_num_t cluster_client_t::select_nearest_osd(const std::vector<osd_num_t> & os
        }
        else
        {
-            auto & peer_state = st_cli.peer_states[osd_num];
+            auto & peer_state = st_cli->peer_states[osd_num];
            if (!peer_state.is_null())
            {
                metric = self_tree_metrics[""];
@@ -539,7 +539,7 @@ osd_num_t cluster_client_t::select_nearest_osd(const std::vector<osd_num_t> & os
                while (seen.find(cur_id) == seen.end())
                {
                    seen.insert(cur_id);
-                    json11::Json cur_placement = st_cli.node_placement[cur_id];
+                    json11::Json cur_placement = st_cli->node_placement[cur_id];
                    std::string cur_parent = cur_placement["parent"].string_value();
                    cur_id = (!first || cur_parent != "" ? cur_parent : peer_state["host"].string_value());
                    first = false;
@@ -564,7 +564,7 @@ osd_num_t cluster_client_t::select_nearest_osd(const std::vector<osd_num_t> & os

 void cluster_client_t::on_load_pgs_hook(bool success)
 {
-    for (auto & pool_item: st_cli.pool_config)
+    for (auto & pool_item: st_cli->pool_config)
    {
        pg_counts[pool_item.first] = pool_item.second.real_pg_count;
    }
@@ -584,13 +584,13 @@ void cluster_client_t::on_load_pgs_hook(bool success)

 void cluster_client_t::on_change_pool_config_hook()
 {
-    for (auto & pool_item: st_cli.pool_config)
+    for (auto & pool_item: st_cli->pool_config)
    {
        if (pg_counts[pool_item.first] != pool_item.second.real_pg_count)
        {
            if (log_level > 2 && pg_counts[pool_item.first])
            {
-                printf("Pool %u (%s) PG count changed from %lu to %lu\n", pool_item.first, pool_item.second.name.c_str(),
+                fprintf(stderr, "Pool %u (%s) PG count changed from %lu to %lu\n", pool_item.first, pool_item.second.name.c_str(),
                    pg_counts[pool_item.first], pool_item.second.real_pg_count);
            }
            // At this point, all pool operations should have been suspended
@@ -612,7 +612,7 @@ void cluster_client_t::on_change_pool_config_hook()

 void cluster_client_t::on_change_pg_state_hook(pool_id_t pool_id, pg_num_t pg_num, osd_num_t prev_primary)
 {
-    auto & pg_cfg = st_cli.pool_config[pool_id].pg_config[pg_num];
+    auto & pg_cfg = st_cli->pool_config[pool_id].pg_config[pg_num];
    if (pg_cfg.cur_primary != prev_primary)
    {
        // Repeat this PG operations because an OSD which stopped being primary may not fsync operations
@@ -630,8 +630,8 @@ bool cluster_client_t::get_immediate_commit(uint64_t inode)
    pool_id_t pool_id = INODE_POOL(inode);
    if (!pool_id)
        return true;
-    auto pool_it = st_cli.pool_config.find(pool_id);
-    if (pool_it == st_cli.pool_config.end())
+    auto pool_it = st_cli->pool_config.find(pool_id);
+    if (pool_it == st_cli->pool_config.end())
        return true;
    return pool_it->second.immediate_commit == IMMEDIATE_ALL;
 }
@@ -641,7 +641,7 @@ void cluster_client_t::on_change_osd_state_hook(uint64_t peer_osd)
    osd_tree_metrics.erase(peer_osd);
    if (msgr.wanted_peers.find(peer_osd) != msgr.wanted_peers.end())
    {
-        msgr.connect_peer(peer_osd, st_cli.peer_states[peer_osd]);
+        msgr.connect_peer(peer_osd, st_cli->peer_states[peer_osd]);
        continue_lists();
    }
 }
@@ -868,15 +868,16 @@ void cluster_client_t::execute_cas(cluster_op_t *op)
    {
        int expected = part->req.hdr.opcode == OSD_OP_DELETE ? 0 : part->req.rw.len;
        op->retval = part->reply.hdr.retval;
-        op->retval = op->retval == expected ? 0 : (op->retval >= 0 ? -EIO : op->retval);
+        if (op->retval != expected && op->retval >= 0)
+            op->retval = -EIO;
        op->retval = op->retval == -EPIPE ? -EINTR : op->retval;
-        auto peer_it = msgr.osd_peer_fds.find(op->parts[0].osd_num);
+        auto peer_it = msgr.osd_peers.find(op->parts[0].osd_num);
        if (op->retval != 0 || (op->flags & OP_IMMEDIATE_COMMIT))
        {
            auto cb = std::move(op->callback);
            cb(op);
        }
-        else if (peer_it == msgr.osd_peer_fds.end())
+        else if (peer_it == msgr.osd_peers.end())
        {
            // Care must be taken to make sure that the client doesn't reconnect to the OSD
            // before executing the previously completed operation callback (!)
@@ -887,20 +888,23 @@ void cluster_client_t::execute_cas(cluster_op_t *op)
        else
        {
            // CAS writes have a built-in sync
-            auto peer_fd = peer_it->second;
+            osd_client_t *cl = peer_it->second;
            *part = (osd_op_t){
                .op_type = OSD_OP_OUT,
-                .peer_fd = peer_fd,
+                .client_id = cl->client_id,
                .req = {
                    .hdr = {
                        .magic = SECONDARY_OSD_OP_MAGIC,
                        .opcode = OSD_OP_SYNC,
                    },
                },
-                .callback = [this, op](osd_op_t *part)
+                .callback = [op](osd_op_t *part)
                {
-                    op->retval = part->reply.hdr.retval;
-                    op->retval = op->retval == -EPIPE ? -EINTR : op->retval;
+                    if (part->reply.hdr.retval != 0)
+                    {
+                        op->retval = part->reply.hdr.retval;
+                        op->retval = op->retval == -EPIPE ? -EINTR : op->retval;
+                    }
                    auto cb = std::move(op->callback);
                    cb(op);
                },
@@ -932,8 +936,8 @@ bool cluster_client_t::check_rw(cluster_op_t *op)
        cb(op);
        return false;
    }
-    auto pool_it = st_cli.pool_config.find(pool_id);
-    if (pool_it == st_cli.pool_config.end() || pool_it->second.real_pg_count == 0)
+    auto pool_it = st_cli->pool_config.find(pool_id);
+    if (pool_it == st_cli->pool_config.end() || pool_it->second.real_pg_count == 0)
    {
        // Pools are loaded, but this one is unknown
        op->retval = -EINVAL;
@@ -956,8 +960,8 @@ bool cluster_client_t::check_rw(cluster_op_t *op)
    }
    if ((op->opcode == OSD_OP_WRITE || op->opcode == OSD_OP_DELETE) && !(op->flags & OSD_OP_IGNORE_READONLY))
    {
-        auto ino_it = st_cli.inode_config.find(op->inode);
-        if (ino_it != st_cli.inode_config.end() && ino_it->second.readonly)
+        auto ino_it = st_cli->inode_config.find(op->inode);
+        if (ino_it != st_cli->inode_config.end() && ino_it->second.readonly)
        {
            op->retval = -EROFS;
            auto cb = std::move(op->callback);
@@ -968,15 +972,15 @@ bool cluster_client_t::check_rw(cluster_op_t *op)
    op->deoptimise_snapshot = false;
    if (enable_writeback && (op->opcode == OSD_OP_READ || op->opcode == OSD_OP_READ_BITMAP || op->opcode == OSD_OP_READ_CHAIN_BITMAP))
    {
-        auto ino_it = st_cli.inode_config.find(op->inode);
-        if (ino_it != st_cli.inode_config.end())
+        auto ino_it = st_cli->inode_config.find(op->inode);
+        if (ino_it != st_cli->inode_config.end())
        {
            int chain_size = 0;
-            while (ino_it != st_cli.inode_config.end() && ino_it->second.parent_id)
+            while (ino_it != st_cli->inode_config.end() && ino_it->second.parent_id)
            {
                // Check for loops - FIXME check it in etcd_state_client
                if (ino_it->second.parent_id == op->inode ||
-                    chain_size > st_cli.inode_config.size())
+                    chain_size > st_cli->inode_config.size())
                {
                    op->retval = -EINVAL;
                    auto cb = std::move(op->callback);
@@ -991,7 +995,7 @@ bool cluster_client_t::check_rw(cluster_op_t *op)
                    break;
                }
                chain_size++;
-                ino_it = st_cli.inode_config.find(ino_it->second.parent_id);
+                ino_it = st_cli->inode_config.find(ino_it->second.parent_id);
            }
        }
    }
@@ -1000,17 +1004,17 @@ bool cluster_client_t::check_rw(cluster_op_t *op)

 void cluster_client_t::execute_raw(osd_num_t osd_num, osd_op_t *op)
 {
-    auto fd_it = msgr.osd_peer_fds.find(osd_num);
-    if (fd_it != msgr.osd_peer_fds.end())
+    auto peer_it = msgr.osd_peers.find(osd_num);
+    if (peer_it != msgr.osd_peers.end())
    {
        op->op_type = OSD_OP_OUT;
-        op->peer_fd = fd_it->second;
+        op->client_id = peer_it->second->client_id;
        msgr.outbox_push(op);
    }
    else
    {
        if (msgr.wanted_peers.find(osd_num) == msgr.wanted_peers.end())
-            msgr.connect_peer(osd_num, st_cli.peer_states[osd_num]);
+            msgr.connect_peer(osd_num, st_cli->peer_states[osd_num]);
        raw_ops.emplace(osd_num, op);
    }
 }
@@ -1115,28 +1119,35 @@ resume_2:
        // Finished successfully
        // Even if the PG count has changed in meanwhile we treat it as success
        // because if some operations were invalid for the new PG count we'd get errors
+        if (op->opcode == OSD_OP_READ || op->opcode == OSD_OP_READ_BITMAP || op->opcode == OSD_OP_READ_CHAIN_BITMAP)
+        {
+            // Copy part bitmaps only after finishing all part reads
+            for (auto & part: op->parts)
+                if ((part.flags & (PART_SENT|PART_DONE|PART_VALID)) == (PART_SENT|PART_DONE|PART_VALID))
+                    copy_part_bitmap(op, &part);
+        }
        if (op->opcode == OSD_OP_READ || op->opcode == OSD_OP_READ_CHAIN_BITMAP)
        {
            // Check parent inode
-            auto ino_it = st_cli.inode_config.find(op->cur_inode);
+            auto ino_it = st_cli->inode_config.find(op->cur_inode);
            // Skip parents from the same pool
            int skipped = 0;
            while (!op->deoptimise_snapshot &&
-                ino_it != st_cli.inode_config.end() && ino_it->second.parent_id &&
+                ino_it != st_cli->inode_config.end() && ino_it->second.parent_id &&
                INODE_POOL(ino_it->second.parent_id) == INODE_POOL(op->cur_inode))
            {
                // Check for loops - FIXME check it in etcd_state_client
                if (ino_it->second.parent_id == op->inode ||
-                    skipped > st_cli.inode_config.size())
+                    skipped > st_cli->inode_config.size())
                {
                    op->retval = -EINVAL;
                    erase_op(op);
                    return 1;
                }
                skipped++;
-                ino_it = st_cli.inode_config.find(ino_it->second.parent_id);
+                ino_it = st_cli->inode_config.find(ino_it->second.parent_id);
            }
-            if (ino_it != st_cli.inode_config.end() &&
+            if (ino_it != st_cli->inode_config.end() &&
                ino_it->second.parent_id &&
                ino_it->second.parent_id != op->inode)
            {
@@ -1150,7 +1161,7 @@ resume_2:
        op->retval = op->len;
        if (op->opcode == OSD_OP_READ_BITMAP || op->opcode == OSD_OP_READ_CHAIN_BITMAP)
        {
-            auto & pool_cfg = st_cli.pool_config.at(INODE_POOL(op->inode));
+            auto & pool_cfg = st_cli->pool_config.at(INODE_POOL(op->inode));
            op->retval = op->len / pool_cfg.bitmap_granularity;
        }
        if (op->flush_id)
@@ -1160,7 +1171,7 @@ resume_2:
        erase_op(op);
        return 1;
    }
-    else if (op->retval != 0 && !(op->flags & OP_FLUSH_BUFFER) &&
+    else if (op->retval != 0 && op->opcode != OSD_OP_SYNC && !(op->flags & OP_FLUSH_BUFFER) &&
        op->retval != -EPIPE && (op->retval != -EIO || !client_eio_retry_interval) && (op->retval != -ENOSPC || !client_retry_enospc))
    {
        // Fatal error (neither -EPIPE, -EIO nor -ENOSPC)
@@ -1236,7 +1247,7 @@ void cluster_client_t::slice_rw(cluster_op_t *op)
 {
    // Slice the request into individual object stripe requests
    // Primary OSDs still operate individual stripes, but their size is multiplied by PG minsize in case of EC
-    auto & pool_cfg = st_cli.pool_config.at(INODE_POOL(op->cur_inode));
+    auto & pool_cfg = st_cli->pool_config.at(INODE_POOL(op->cur_inode));
    uint32_t pg_data_size = (pool_cfg.scheme == POOL_SCHEME_REPLICATED ? 1 : pool_cfg.pg_size-pool_cfg.parity_chunks);
    uint64_t pg_block_size = pool_cfg.data_block_size * pg_data_size;
    uint64_t first_stripe = (op->offset / pg_block_size) * pg_block_size;
@@ -1253,9 +1264,9 @@ void cluster_client_t::slice_rw(cluster_op_t *op)
        {
            op->bitmap_buf = realloc_or_die(op->bitmap_buf, bitmap_mem);
            op->part_bitmaps = (uint8_t*)op->bitmap_buf + object_bitmap_size;
+            memset((uint8_t*)op->bitmap_buf+op->bitmap_buf_size, 0, bitmap_mem-op->bitmap_buf_size);
            op->bitmap_buf_size = bitmap_mem;
        }
-        memset(op->bitmap_buf, 0, bitmap_mem);
    }
    int iov_idx = 0;
    size_t iov_pos = 0;
@@ -1335,7 +1346,7 @@ bool cluster_client_t::affects_pg(uint64_t inode, uint64_t offset, uint64_t len,
    {
        return false;
    }
-    auto & pool_cfg = st_cli.pool_config.at(INODE_POOL(inode));
+    auto & pool_cfg = st_cli->pool_config.at(INODE_POOL(inode));
    uint32_t pg_data_size = (pool_cfg.scheme == POOL_SCHEME_REPLICATED ? 1 : pool_cfg.pg_size-pool_cfg.parity_chunks);
    uint64_t pg_block_size = pool_cfg.data_block_size * pg_data_size;
    uint64_t first_stripe = (offset / pg_block_size) * pg_block_size;
@@ -1354,7 +1365,7 @@ bool cluster_client_t::affects_pg(uint64_t inode, uint64_t offset, uint64_t len,

 bool cluster_client_t::affects_osd(uint64_t inode, uint64_t offset, uint64_t len, osd_num_t osd)
 {
-    auto & pool_cfg = st_cli.pool_config.at(INODE_POOL(inode));
+    auto & pool_cfg = st_cli->pool_config.at(INODE_POOL(inode));
    uint32_t pg_data_size = (pool_cfg.scheme == POOL_SCHEME_REPLICATED ? 1 : pool_cfg.pg_size-pool_cfg.parity_chunks);
    uint64_t pg_block_size = pool_cfg.data_block_size * pg_data_size;
    uint64_t first_stripe = (offset / pg_block_size) * pg_block_size;
@@ -1378,7 +1389,7 @@ int cluster_client_t::try_send(cluster_op_t *op, int i, std::function<void(osd_o
        init_msgr();
    }
    auto part = &op->parts[i];
-    auto & pool_cfg = st_cli.pool_config.at(INODE_POOL(op->cur_inode));
+    auto & pool_cfg = st_cli->pool_config.at(INODE_POOL(op->cur_inode));
    auto pg_it = pool_cfg.pg_config.find(part->pg_num);
    if (pg_it != pool_cfg.pg_config.end() &&
        !pg_it->second.pause && pg_it->second.cur_primary &&
@@ -1397,11 +1408,11 @@ int cluster_client_t::try_send(cluster_op_t *op, int i, std::function<void(osd_o
                primary_osd = nearest_osd;
        }
        part->osd_num = primary_osd;
-        auto peer_it = msgr.osd_peer_fds.find(primary_osd);
-        if (peer_it != msgr.osd_peer_fds.end())
+        auto peer_it = msgr.osd_peers.find(primary_osd);
+        if (peer_it != msgr.osd_peers.end())
        {
-            int peer_fd = peer_it->second;
-            part->flags |= PART_SENT;
+            osd_client_t *cl = peer_it->second;
+            part->flags |= PART_SENT|PART_VALID;
            op->inflight_count++;
            uint64_t pg_bitmap_size = (pool_cfg.data_block_size / pool_cfg.bitmap_granularity / 8) * (
                pool_cfg.scheme == POOL_SCHEME_REPLICATED ? 1 : pool_cfg.pg_size-pool_cfg.parity_chunks
@@ -1409,13 +1420,13 @@ int cluster_client_t::try_send(cluster_op_t *op, int i, std::function<void(osd_o
            uint64_t meta_rev = 0;
            if (op->opcode != OSD_OP_READ_BITMAP && op->opcode != OSD_OP_DELETE && !op->deoptimise_snapshot)
            {
-                auto ino_it = st_cli.inode_config.find(op->cur_inode);
-                if (ino_it != st_cli.inode_config.end())
+                auto ino_it = st_cli->inode_config.find(op->cur_inode);
+                if (ino_it != st_cli->inode_config.end())
                    meta_rev = ino_it->second.mod_revision;
            }
            part->op = (osd_op_t){
                .op_type = OSD_OP_OUT,
-                .peer_fd = peer_fd,
+                .client_id = cl->client_id,
                .req = { .rw = {
                    .header = {
                        .magic = SECONDARY_OSD_OP_MAGIC,
@@ -1442,7 +1453,7 @@ int cluster_client_t::try_send(cluster_op_t *op, int i, std::function<void(osd_o
        }
        else if (msgr.wanted_peers.find(primary_osd) == msgr.wanted_peers.end())
        {
-            msgr.connect_peer(primary_osd, st_cli.peer_states[primary_osd]);
+            msgr.connect_peer(primary_osd, st_cli->peer_states[primary_osd]);
            return TRY_SEND_CONNECTING;
        }
    }
@@ -1464,8 +1475,8 @@ int cluster_client_t::continue_sync(cluster_op_t *op)
    for (auto do_it = dirty_osds.begin(); do_it != dirty_osds.end(); )
    {
        osd_num_t sync_osd = *do_it;
-        auto peer_it = msgr.osd_peer_fds.find(sync_osd);
-        if (peer_it == msgr.osd_peer_fds.end())
+        auto peer_it = msgr.osd_peers.find(sync_osd);
+        if (peer_it == msgr.osd_peers.end())
            dirty_osds.erase(do_it++);
        else
            do_it++;
@@ -1518,12 +1529,12 @@ resume_1:

 void cluster_client_t::send_sync(cluster_op_t *op, cluster_op_part_t *part)
 {
-    auto peer_fd = msgr.osd_peer_fds.at(part->osd_num);
+    osd_client_t *cl = msgr.osd_peers.at(part->osd_num);
    part->flags |= PART_SENT;
    op->inflight_count++;
    part->op = (osd_op_t){
        .op_type = OSD_OP_OUT,
-        .peer_fd = peer_fd,
+        .client_id = cl->client_id,
        .req = {
            .hdr = {
                .magic = SECONDARY_OSD_OP_MAGIC,
@@ -1563,10 +1574,10 @@ void cluster_client_t::handle_op_part(cluster_op_part_t *part)
            // Error priority: EIO > ENOSPC > ETIMEDOUT > EPIPE
            op->retval = part->op.reply.hdr.retval;
        }
-        int stop_fd = -1;
+        uint64_t stop_client_id = 0;
        if (op->retval != -EINTR && op->retval != -EIO && op->retval != -ENOSPC)
        {
-            stop_fd = part->op.peer_fd;
+            stop_client_id = part->op.client_id;
            if (op->retval != -EPIPE || log_level > 0)
            {
                fprintf(
@@ -1593,9 +1604,9 @@ void cluster_client_t::handle_op_part(cluster_op_part_t *part)
            op->retry_after = op->retval != -EPIPE ? client_eio_retry_interval : client_retry_interval;
        }
        reset_retry_timer(op->retry_after);
-        if (stop_fd >= 0)
+        if (stop_client_id)
        {
-            msgr.stop_client(stop_fd);
+            msgr.stop_client(stop_client_id);
        }
        op->inflight_count--;
        if (op->inflight_count == 0 && !op->retry_after)
@@ -1614,14 +1625,11 @@ void cluster_client_t::handle_op_part(cluster_op_part_t *part)
            dirty_osds.insert(part->osd_num);
        part->flags |= PART_DONE;
        op->done_count++;
-        if (op->opcode == OSD_OP_READ || op->opcode == OSD_OP_READ_BITMAP || op->opcode == OSD_OP_READ_CHAIN_BITMAP)
+        if ((op->opcode == OSD_OP_READ || op->opcode == OSD_OP_READ_BITMAP || op->opcode == OSD_OP_READ_CHAIN_BITMAP)
+            && op->inode == op->cur_inode)
        {
-            copy_part_bitmap(op, part);
-            if (op->inode == op->cur_inode)
-            {
-                // Read only returns the version of the uppermost layer
-                op->version = op->parts.size() == 1 ? part->op.reply.rw.version : 0;
-            }
+            // Read only returns the version of the uppermost layer
+            op->version = op->parts.size() == 1 ? part->op.reply.rw.version : 0;
        }
        else if (op->opcode == OSD_OP_WRITE || op->opcode == OSD_OP_DELETE)
        {
@@ -1640,7 +1648,7 @@ void cluster_client_t::handle_op_part(cluster_op_part_t *part)
 void cluster_client_t::copy_part_bitmap(cluster_op_t *op, cluster_op_part_t *part)
 {
    // Copy (OR) bitmap
-    auto & pool_cfg = st_cli.pool_config.at(INODE_POOL(op->cur_inode));
+    auto & pool_cfg = st_cli->pool_config.at(INODE_POOL(op->cur_inode));
    uint32_t pg_block_size = pool_cfg.data_block_size * (
        pool_cfg.scheme == POOL_SCHEME_REPLICATED ? 1 : pool_cfg.pg_size-pool_cfg.parity_chunks
    );
@@ -4,7 +4,7 @@
 #pragma once

 #include "messenger.h"
-#include "etcd_state_client.h"
+#include "etcd_state_client_http.h"

 #define DEFAULT_CLIENT_MAX_DIRTY_BYTES 32*1024*1024
 #define DEFAULT_CLIENT_MAX_DIRTY_OPS 1024
@@ -83,9 +83,6 @@ class writeback_cache_t;
 // FIXME: Split into public and private interfaces
 class __attribute__((visibility("default"))) cluster_client_t
 {
-#ifdef __MOCK__
-public:
-#endif
    timerfd_manager_t *tfd = NULL;
    ring_loop_t *ringloop = NULL;

@@ -134,7 +131,7 @@ public:
    bool msgr_initialized = false;

 public:
-    etcd_state_client_t st_cli;
+    std::unique_ptr<etcd_state_client_t> st_cli;

    osd_messenger_t msgr;
    void init_msgr();
@@ -142,7 +139,8 @@ public:
    json11::Json::object cli_config, file_config, etcd_global_config;
    json11::Json::object config;

-    cluster_client_t(ring_loop_t *ringloop, timerfd_manager_t *tfd, json11::Json config);
+    static cluster_client_t* create(ring_loop_t *ringloop, timerfd_manager_t *tfd, json11::Json config);
+    cluster_client_t(ring_loop_t *ringloop, timerfd_manager_t *tfd, json11::Json config, std::unique_ptr<etcd_state_client_t> st_cli);
    ~cluster_client_t();
    void execute(cluster_op_t *op);
    void execute_raw(osd_num_t osd_num, osd_op_t *op);
@@ -155,15 +153,9 @@ public:
    void list_inode(inode_t inode, uint64_t min_offset, uint64_t max_offset, int max_parallel_pgs, std::function<void(
        int status, int pgs_left, pg_num_t pg_num, std::set<object_id>&& objects)> pg_callback);

-    //inline uint32_t get_bs_bitmap_granularity() { return st_cli.global_bitmap_granularity; }
-    //inline uint64_t get_bs_block_size() { return st_cli.global_block_size; }
-
-#ifndef __MOCK__
 protected:
-#endif
    void continue_ops(int time_passed = 0);

-protected:
    bool affects_osd(uint64_t inode, uint64_t offset, uint64_t len, osd_num_t osd);
    bool affects_pg(uint64_t inode, uint64_t offset, uint64_t len, pool_id_t pool_id, pg_num_t pg_num);

@@ -204,4 +196,5 @@ protected:
    osd_num_t select_nearest_osd(const std::vector<osd_num_t> & osds);

    friend class writeback_cache_t;
+    friend class cluster_client_test_t;
 };
@@ -10,6 +10,7 @@
 #define PART_DONE 2
 #define PART_ERROR 4
 #define PART_RETRY 8
+#define PART_VALID 16
 #define CACHE_DIRTY 1
 #define CACHE_WRITTEN 2
 #define CACHE_FLUSHING 3
--- a/Show More
+++ b/Show More