Attempt journal trim even without new flushes

This is the new guaranteed unblocking method which replaces old trims
in init and rollback, and also fixes a possible stall when just several
writes in the beginning of the journal are flushed without triggering
a subsequent trim.
Vitaliy Filippov 2020-10-24 00:52:21 +03:00
förälder 5fbe36198a
incheckning faa5e1436f
4 ändrade filer med 35 tillägg och 14 borttagningar

Visa fil

@ -15,6 +15,7 @@ journal_flusher_t::journal_flusher_t(int flusher_count, blockstore_impl_t *bs)
flusher_start_threshold = bs->journal_block_size / sizeof(journal_entry_stable);
journal_trim_interval = 512;
journal_trim_counter = 0;
trim_wanted = 0;
journal_superblock = bs->journal.inmemory ? bs->journal.buffer : memalign_or_die(MEM_ALIGNMENT, bs->journal_block_size);
co = new journal_flusher_co[flusher_count];
for (int i = 0; i < flusher_count; i++)
@ -86,7 +87,7 @@ void journal_flusher_t::enqueue_flush(obj_ver_id ov)
flush_versions[ov.oid] = ov.version;
flush_queue.push_back(ov.oid);
}
if (!dequeuing && flush_queue.size() >= flusher_start_threshold)
if (!dequeuing && (flush_queue.size() >= flusher_start_threshold || trim_wanted > 0))
{
dequeuing = true;
bs->ringloop->wakeup();
@ -106,7 +107,7 @@ void journal_flusher_t::unshift_flush(obj_ver_id ov)
flush_versions[ov.oid] = ov.version;
flush_queue.push_front(ov.oid);
}
if (!dequeuing && flush_queue.size() >= flusher_start_threshold)
if (!dequeuing && (flush_queue.size() >= flusher_start_threshold || trim_wanted > 0))
{
dequeuing = true;
bs->ringloop->wakeup();
@ -120,6 +121,16 @@ void journal_flusher_t::request_trim()
bs->ringloop->wakeup();
}
void journal_flusher_t::mark_trim_possible()
{
if (trim_wanted > 0)
{
dequeuing = true;
journal_trim_counter++;
bs->ringloop->wakeup();
}
}
void journal_flusher_t::release_trim()
{
trim_wanted--;
@ -183,6 +194,12 @@ bool journal_flusher_co::loop()
resume_0:
if (!flusher->flush_queue.size() || !flusher->dequeuing)
{
if (flusher->trim_wanted > 0 && flusher->journal_trim_counter > 0)
{
// Attempt forced trim
flusher->active_flushers++;
goto trim_journal;
}
flusher->dequeuing = false;
wait_state = 0;
return true;
@ -307,7 +324,7 @@ resume_1:
{
// Nothing to flush
bs->erase_dirty(dirty_start, std::next(dirty_end), clean_loc);
goto trim_journal;
goto release_oid;
}
if (clean_loc == UINT64_MAX)
{
@ -487,6 +504,18 @@ resume_1:
}
// Update clean_db and dirty_db, free old data locations
update_clean_db();
#ifdef BLOCKSTORE_DEBUG
printf("Flushed %lx:%lx v%lu (%d copies, wr:%d, del:%d), %ld left\n", cur.oid.inode, cur.oid.stripe, cur.version,
copy_count, has_writes, has_delete, flusher->flush_queue.size());
#endif
release_oid:
repeat_it = flusher->sync_to_repeat.find(cur.oid);
if (repeat_it != flusher->sync_to_repeat.end() && repeat_it->second > cur.version)
{
// Requeue version
flusher->unshift_flush({ .oid = cur.oid, .version = repeat_it->second });
}
flusher->sync_to_repeat.erase(repeat_it);
trim_journal:
// Clear unused part of the journal every <journal_trim_interval> flushes
if (!((++flusher->journal_trim_counter) % flusher->journal_trim_interval) || flusher->trim_wanted > 0)
@ -545,18 +574,7 @@ resume_1:
}
}
// All done
#ifdef BLOCKSTORE_DEBUG
printf("Flushed %lx:%lx v%lu (%d copies, wr:%d, del:%d), %ld left\n", cur.oid.inode, cur.oid.stripe, cur.version,
copy_count, has_writes, has_delete, flusher->flush_queue.size());
#endif
flusher->active_flushers--;
repeat_it = flusher->sync_to_repeat.find(cur.oid);
if (repeat_it != flusher->sync_to_repeat.end() && repeat_it->second > cur.version)
{
// Requeue version
flusher->unshift_flush({ .oid = cur.oid, .version = repeat_it->second });
}
flusher->sync_to_repeat.erase(repeat_it);
wait_state = 0;
goto resume_0;
}

Visa fil

@ -103,6 +103,7 @@ public:
~journal_flusher_t();
void loop();
bool is_active();
void mark_trim_possible();
void request_trim();
void release_trim();
void enqueue_flush(obj_ver_id oid);

Visa fil

@ -399,6 +399,7 @@ resume_1:
}
}
}
bs->flusher->mark_trim_possible();
bs->journal.dirty_start = bs->journal.next_free;
printf(
"Journal entries loaded: %lu, free journal space: %lu bytes (%08lx..%08lx is used), free blocks: %lu / %lu\n",

Visa fil

@ -148,6 +148,7 @@ resume_5:
{
mark_rolled_back(*v);
}
flusher->mark_trim_possible();
// Acknowledge op
op->retval = 0;
FINISH_OP(op);