thebestvibedev/tromcho.net
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Finish sync algorithm in theory

Browse Source
This commit is contained in:
Vitaliy Filippov
2019-11-10 12:52:37 +03:00
parent 24f5d71595
commit ae56fe1067
4 changed files with 109 additions and 63 deletions
Download Patch File Download Diff File Expand all files Collapse all files
blockstore_sync.cpp
+73 -41
View File
@@ -3,33 +3,42 @@
#define SYNC_NO_BIG 1
#define SYNC_HAS_BIG 2
#define SYNC_DATA_SYNC_SENT 3
#define SYNC_JOURNAL_SYNC_SENT 4
#define SYNC_DONE 5
#define SYNC_DATA_SYNC_DONE 4
#define SYNC_JOURNAL_SYNC_SENT 5
#define SYNC_DONE 6
int blockstore::dequeue_sync(blockstore_operation *op)
{
if (op->sync_state == 0)
{
op->big_write_count = 0;
op->sync_state = SYNC_NO_BIG;
op->sync_writes.swap(unsynced_writes);
unsynced_writes.clear();
if (op->sync_writes.size() == 0)
{
op->sync_big_writes.swap(unsynced_big_writes);
op->big_write_count = op->sync_big_writes.size();
if (op->big_write_count > 0)
op->sync_state = SYNC_HAS_BIG;
else if (unsynced_small_writes == 0)
op->sync_state = SYNC_DONE;
}
auto it = op->sync_writes.begin();
while (it != op->sync_writes.end())
else
op->sync_state = SYNC_NO_BIG;
unsynced_big_writes.clear();
unsynced_small_writes = 0;
}
int r = continue_sync(op);
if (r)
{
int done = ack_sync(op);
if (!done)
{
uint32_t state = dirty_db[*it].state;
if (IS_BIG_WRITE(state))
{
op->big_write_count++;
op->sync_state = SYNC_HAS_BIG;
}
it++;
in_progress_ops.insert(op);
op->prev_sync_count = in_progress_syncs.size();
op->in_progress_ptr = in_progress_syncs.insert(in_progress_syncs.end(), op);
}
}
return r;
}
int blockstore::continue_sync(blockstore_operation *op)
{
if (op->sync_state == SYNC_NO_BIG)
{
// No big writes, just fsync the journal
@@ -48,7 +57,7 @@ int blockstore::dequeue_sync(blockstore_operation *op)
op->pending_ops = 1;
op->sync_state = SYNC_DATA_SYNC_SENT;
}
else if (op->sync_state == SYNC_DATA_SYNC_SENT)
else if (op->sync_state == SYNC_DATA_SYNC_DONE)
{
// 2nd step: Data device is synced, prepare & write journal entries
// Check space in the journal and journal memory buffers
@@ -87,8 +96,7 @@ int blockstore::dequeue_sync(blockstore_operation *op)
op->min_used_journal_sector = 1 + journal.cur_sector;
sectors_required = 0;
required = op->big_write_count;
// FIXME: advance it
auto it = op->sync_writes.begin();
auto it = op->sync_big_writes.begin();
while (1)
{
int fits = (512 - journal.in_sector_pos) / sizeof(journal_entry_big_write);
@@ -111,6 +119,7 @@ int blockstore::dequeue_sync(blockstore_operation *op)
journal.crc32_last = je->crc32;
journal.in_sector_pos += sizeof(journal_entry_big_write);
required--;
it++;
}
if (required <= 0)
break;
@@ -136,9 +145,10 @@ int blockstore::dequeue_sync(blockstore_operation *op)
op->max_used_journal_sector = 1 + journal.cur_sector;
op->sync_state = SYNC_JOURNAL_SYNC_SENT;
}
// FIXME: resubmit op from in_progress
op->prev_sync_count = in_progress_syncs.size();
op->in_progress_ptr = in_progress_syncs.insert(in_progress_syncs.end(), op);
else
{
return 0;
}
return 1;
}
@@ -151,40 +161,62 @@ void blockstore::handle_sync_event(ring_data_t *data, blockstore_operation *op)
throw new std::runtime_error("write operation failed. in-memory state is corrupted. AAAAAAAaaaaaaaaa!!!111");
}
op->pending_ops--;
if (op->min_used_journal_sector > 0)
{
for (uint64_t s = op->min_used_journal_sector; s != op->max_used_journal_sector; s = (s + 1) % journal.sector_count)
{
journal.sector_info[s-1].usage_count--;
}
op->min_used_journal_sector = op->max_used_journal_sector = 0;
}
if (op->pending_ops == 0)
{
// Acknowledge sync
// Release used journal sectors
if (op->min_used_journal_sector > 0)
{
for (uint64_t s = op->min_used_journal_sector; s != op->max_used_journal_sector; s = (s + 1) % journal.sector_count)
{
journal.sector_info[s-1].usage_count--;
}
op->min_used_journal_sector = op->max_used_journal_sector = 0;
}
// Handle state
if (op->sync_state == SYNC_DATA_SYNC_SENT)
{
op->sync_state = SYNC_DATA_SYNC_DONE;
}
else if (op->sync_state == SYNC_JOURNAL_SYNC_SENT)
{
op->sync_state = SYNC_DONE;
}
else
{
throw new std::runtime_error("BUG: unexpected sync op state");
}
ack_sync(op);
}
}
int blockstore::ack_sync(blockstore_operation *op)
{
if (op->sync_state == SYNC_DONE && op->prev_sync_count == 0)
{
// Remove dependency of subsequent syncs
auto it = op->in_progress_ptr;
int done_syncs = 1;
++it;
while (it != in_progress_syncs.end())
{
auto & next_sync = *it;
auto & next_sync = *it++;
next_sync->prev_sync_count -= done_syncs;
if (next_sync->prev_sync_count == 0/* && next_sync->DONE*/)
if (next_sync->prev_sync_count == 0 && next_sync->sync_state == SYNC_DONE)
{
done_syncs++;
auto next_it = it;
it++;
in_progress_syncs.erase(next_it);
// Acknowledge next_sync
in_progress_syncs.erase(next_sync->in_progress_ptr);
in_progress_ops.erase(next_sync);
next_sync->retval = 0;
next_sync->callback(next_sync);
in_progress_ops.erase(next_sync);
}
else
it++;
}
// Acknowledge sync
in_progress_syncs.erase(op->in_progress_ptr);
in_progress_ops.erase(op);
op->retval = 0;
op->callback(op);
in_progress_ops.erase(op);
return 1;
}
return 0;
}