Details
-
Bug
-
Status: Closed (View Workflow)
-
Major
-
Resolution: Fixed
-
10.2.2, 10.3.0
-
10.2.14
Description
The flush_counters_t that were introduced in MDEV-6936 were broken in the merge of InnoDB from MySQL 5.7.9 to MariaDB 10.2.2. After that change, the function buf_flush_LRU_list_batch() initializes all counts to 0 and will not update them.
I would fix this as follows. I still need to figure out how to add a regression test for this.
diff --git a/storage/innobase/buf/buf0flu.cc b/storage/innobase/buf/buf0flu.cc
|
index e938c27cfec..17f915a9d12 100644
|
--- a/storage/innobase/buf/buf0flu.cc
|
+++ b/storage/innobase/buf/buf0flu.cc
|
@@ -1654,8 +1654,6 @@ buf_flush_LRU_list_batch(
|
{
|
buf_page_t* bpage;
|
ulint scanned = 0;
|
- ulint evict_count = 0;
|
- ulint count = 0;
|
ulint free_len = UT_LIST_GET_LEN(buf_pool->free);
|
ulint lru_len = UT_LIST_GET_LEN(buf_pool->LRU);
|
ulint withdraw_depth = 0;
|
@@ -1671,7 +1669,7 @@ buf_flush_LRU_list_batch(
|
}
|
|
for (bpage = UT_LIST_GET_LAST(buf_pool->LRU);
|
- bpage != NULL && count + evict_count < max
|
+ bpage != NULL && n->flushed + n->evicted < max
|
&& free_len < srv_LRU_scan_depth + withdraw_depth
|
&& lru_len > BUF_LRU_MIN_LEN;
|
++scanned,
|
@@ -1689,7 +1687,7 @@ buf_flush_LRU_list_batch(
|
clean and is not IO-fixed or buffer fixed. */
|
mutex_exit(block_mutex);
|
if (buf_LRU_free_page(bpage, true)) {
|
- ++evict_count;
|
+ ++n->evicted;
|
}
|
} else if (buf_flush_ready_for_flush(bpage, BUF_FLUSH_LRU)) {
|
/* Block is ready for flush. Dispatch an IO
|
@@ -1697,7 +1695,7 @@ buf_flush_LRU_list_batch(
|
free list in IO completion routine. */
|
mutex_exit(block_mutex);
|
buf_flush_page_and_try_neighbors(
|
- bpage, BUF_FLUSH_LRU, max, &count);
|
+ bpage, BUF_FLUSH_LRU, max, &n->flushed);
|
} else {
|
/* Can't evict or dispatch this block. Go to
|
previous. */
|
@@ -1721,12 +1719,12 @@ buf_flush_LRU_list_batch(
|
|
ut_ad(buf_pool_mutex_own(buf_pool));
|
|
- if (evict_count) {
|
+ if (n->evicted) {
|
MONITOR_INC_VALUE_CUMULATIVE(
|
MONITOR_LRU_BATCH_EVICT_TOTAL_PAGE,
|
MONITOR_LRU_BATCH_EVICT_COUNT,
|
MONITOR_LRU_BATCH_EVICT_PAGES,
|
- evict_count);
|
+ n->evicted);
|
}
|
|
if (scanned) {
|
@@ -2182,17 +2180,16 @@ buf_flush_lists(
|
help in the retry which will follow the
|
failure. */
|
success = false;
|
-
|
- continue;
|
}
|
+
|
+ n_flushed += n.flushed;
|
}
|
|
if (n_flushed) {
|
buf_flush_stats(n_flushed, 0);
|
- }
|
-
|
- if (n_processed) {
|
- *n_processed = n_flushed;
|
+ if (n_processed) {
|
+ *n_processed = n_flushed;
|
+ }
|
}
|
|
return(success); |
Attachments
Issue Links
- relates to
-
MDEV-6936 Buffer pool list scan optimization
-
- Closed
-
-
-
- Closed
-
Even with the patch, I cannot get a test to report any page flushes:
diff --git a/mysql-test/suite/innodb/t/purge_secondary.test b/mysql-test/suite/innodb/t/purge_secondary.testindex 47cfaec41ca..3ffaa9b9802 100644--- a/mysql-test/suite/innodb/t/purge_secondary.test+++ b/mysql-test/suite/innodb/t/purge_secondary.test@@ -1,5 +1,8 @@--source include/have_innodb.inc+SET GLOBAL innodb_monitor_enable = '%flush%';+SET GLOBAL innodb_monitor_enable = DEFAULT;+# Ensure that the history list length will actually be decremented by purge.SET @saved_frequency = @@GLOBAL.innodb_purge_rseg_truncate_frequency;SET GLOBAL innodb_purge_rseg_truncate_frequency = 1;@@ -121,11 +124,21 @@ SELECT OTHER_INDEX_SIZE FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESTATSWHERE NAME='test/t1';--echo # Note: The OTHER_INDEX_SIZE does not cover any SPATIAL INDEX.---echo # To test that all indexes were emptied, replace DROP TABLE---echo # with the following, and examine the root pages in t1.ibd:---echo # FLUSH TABLES t1 FOR EXPORT;---echo # UNLOCK TABLES;+--echo # To test that all indexes were emptied, remove DROP TABLE+--echo # and examine the root pages in t1.ibd:+FLUSH TABLES t1 FOR EXPORT;+UNLOCK TABLES;DROP TABLE t1;SET GLOBAL innodb_purge_rseg_truncate_frequency = @saved_frequency;++SELECT * FROM information_schema.global_status+WHERE LOWER(variable_name) LIKE 'innodb%flush%';++SELECT name, max_count, min_count, count,+ max_count_reset, min_count_reset, count_reset, status+FROM information_schema.innodb_metrics+WHERE name LIKE '%flush%';+SET GLOBAL innodb_monitor_disable = '%flush%';Please revise this to make this work.
I noticed the problem when working on
MDEV-15053, on the MySQL 8.0 BUG#23102834 INNODB: ZERO FLUSH FROM LRU.Preferrably I would test this in some existing tests, instead of adding a separate big test for this, like the above Oracle change did.
Also, we might want to check INNODB_ENCRYPTION_ROTATION_PAGES_FLUSHED in some of the encryption tests.