Report inode space usage statistics to etcd, aggregate it in the monitor

src/blockstore.cpp

@@ -43,7 +43,7 @@ std::unordered_map<object_id, uint64_t> & blockstore_t::get_unstable_writes()
     return impl->unstable_writes;
 }
 
-std::map<uint64_t, int64_t> & blockstore_t::get_inode_space_stats()
+std::map<uint64_t, uint64_t> & blockstore_t::get_inode_space_stats()
 {
     return impl->inode_space_stats;
 }

src/blockstore.h

@@ -184,7 +184,7 @@ public:
     std::unordered_map<object_id, uint64_t> & get_unstable_writes();
 
     // Get per-inode space usage statistics
-    std::map<uint64_t, int64_t> & get_inode_space_stats();
+    std::map<uint64_t, uint64_t> & get_inode_space_stats();
 
     // FIXME rename to object_size
     uint32_t get_block_size();

src/blockstore_impl.h

@@ -328,7 +328,7 @@ public:
     std::unordered_map<object_id, uint64_t> unstable_writes;
 
     // Space usage statistics
-    std::map<uint64_t, int64_t> inode_space_stats;
+    std::map<uint64_t, uint64_t> inode_space_stats;
 
     inline uint32_t get_block_size() { return block_size; }
     inline uint64_t get_block_count() { return block_count; }

src/osd_cluster.cpp

@@ -180,11 +180,22 @@ void osd_t::report_statistics()
         return;
     }
     etcd_reporting_stats = true;
+    // Report space usage statistics as a whole
+    // Maybe we'll report it using deltas if we tune for a lot of inodes at some point
+    json11::Json::object inode_space;
+    for (auto kv: bs->get_inode_space_stats())
+    {
+        inode_space[std::to_string(kv.first)] = kv.second;
+    }
     json11::Json::array txn = { json11::Json::object {
         { "request_put", json11::Json::object {
             { "key", base64_encode(st_cli.etcd_prefix+"/osd/stats/"+std::to_string(osd_num)) },
             { "value", base64_encode(get_statistics().dump()) },
-        } }
+        } },
+        { "request_put", json11::Json::object {
+            { "key", base64_encode(st_cli.etcd_prefix+"/osd/space/"+std::to_string(osd_num)) },
+            { "value", base64_encode(json11::Json(inode_space).dump()) },
+        } },
     } };
     for (auto & p: pgs)
     {