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MDEV-15822: WSREP: BF lock wait long for trx 
In Galera BF (brute force) transactions may not wait for lock requests
and normally BF-transaction would select transaction holding conflicting
locks as a victim for rollback. However, background statistic calculation
transaction is InnoDB internal transaction and it has no thd i.e. it can't be
selected as a victim. If background statistics calculation transaction holds
conflicting locks to statistics tables it will cause BF lock wait long
error message. Correct way to handle background statistics calculation is to
acquire thd for transaction but that change is too big for GA-releases and
there are other reported problems on background statistics calculation.

This fix avoids adding a table to background statistics calculation if
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Jan Lindström committed Jul 25, 2018
1 parent a0d33dc commit 57cde8c
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Showing 4 changed files with 167 additions and 3 deletions.
95 mysql-test/suite/galera/r/galera_bf_background_statistics.result
View file
@@ -0,0 +1,95 @@
SELECT @@innodb_stats_persistent;
@@innodb_stats_persistent
1
CREATE TABLE t1 (f1 INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY, f2 INTEGER DEFAULT NULL) ENGINE=InnoDB;
INSERT INTO t1(f1) values (NULL);
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
SELECT count(1) from t1;
count(1)
16384
SET AUTOCOMMIT=OFF;
INSERT INTO t1 VALUES (9999999,NULL);
SELECT SLEEP(1000);;
ALTER TABLE t1 CHANGE f2 f2 INTEGER NOT NULL DEFAULT 1;
Warnings:
Warning 1265 Data truncated for column 'f2' at row 1
Warning 1265 Data truncated for column 'f2' at row 2
Warning 1265 Data truncated for column 'f2' at row 3
Warning 1265 Data truncated for column 'f2' at row 4
Warning 1265 Data truncated for column 'f2' at row 5
Warning 1265 Data truncated for column 'f2' at row 6
Warning 1265 Data truncated for column 'f2' at row 7
Warning 1265 Data truncated for column 'f2' at row 8
Warning 1265 Data truncated for column 'f2' at row 9
Warning 1265 Data truncated for column 'f2' at row 10
Warning 1265 Data truncated for column 'f2' at row 11
Warning 1265 Data truncated for column 'f2' at row 12
Warning 1265 Data truncated for column 'f2' at row 13
Warning 1265 Data truncated for column 'f2' at row 14
Warning 1265 Data truncated for column 'f2' at row 15
Warning 1265 Data truncated for column 'f2' at row 16
Warning 1265 Data truncated for column 'f2' at row 17
Warning 1265 Data truncated for column 'f2' at row 18
Warning 1265 Data truncated for column 'f2' at row 19
Warning 1265 Data truncated for column 'f2' at row 20
Warning 1265 Data truncated for column 'f2' at row 21
Warning 1265 Data truncated for column 'f2' at row 22
Warning 1265 Data truncated for column 'f2' at row 23
Warning 1265 Data truncated for column 'f2' at row 24
Warning 1265 Data truncated for column 'f2' at row 25
Warning 1265 Data truncated for column 'f2' at row 26
Warning 1265 Data truncated for column 'f2' at row 27
Warning 1265 Data truncated for column 'f2' at row 28
Warning 1265 Data truncated for column 'f2' at row 29
Warning 1265 Data truncated for column 'f2' at row 30
Warning 1265 Data truncated for column 'f2' at row 31
Warning 1265 Data truncated for column 'f2' at row 32
Warning 1265 Data truncated for column 'f2' at row 33
Warning 1265 Data truncated for column 'f2' at row 34
Warning 1265 Data truncated for column 'f2' at row 35
Warning 1265 Data truncated for column 'f2' at row 36
Warning 1265 Data truncated for column 'f2' at row 37
Warning 1265 Data truncated for column 'f2' at row 38
Warning 1265 Data truncated for column 'f2' at row 39
Warning 1265 Data truncated for column 'f2' at row 40
Warning 1265 Data truncated for column 'f2' at row 41
Warning 1265 Data truncated for column 'f2' at row 42
Warning 1265 Data truncated for column 'f2' at row 43
Warning 1265 Data truncated for column 'f2' at row 44
Warning 1265 Data truncated for column 'f2' at row 45
Warning 1265 Data truncated for column 'f2' at row 46
Warning 1265 Data truncated for column 'f2' at row 47
Warning 1265 Data truncated for column 'f2' at row 48
Warning 1265 Data truncated for column 'f2' at row 49
Warning 1265 Data truncated for column 'f2' at row 50
Warning 1265 Data truncated for column 'f2' at row 51
Warning 1265 Data truncated for column 'f2' at row 52
Warning 1265 Data truncated for column 'f2' at row 53
Warning 1265 Data truncated for column 'f2' at row 54
Warning 1265 Data truncated for column 'f2' at row 55
Warning 1265 Data truncated for column 'f2' at row 56
Warning 1265 Data truncated for column 'f2' at row 57
Warning 1265 Data truncated for column 'f2' at row 58
Warning 1265 Data truncated for column 'f2' at row 59
Warning 1265 Data truncated for column 'f2' at row 60
Warning 1265 Data truncated for column 'f2' at row 61
Warning 1265 Data truncated for column 'f2' at row 62
Warning 1265 Data truncated for column 'f2' at row 63
Warning 1265 Data truncated for column 'f2' at row 64
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
wsrep_local_aborts_increment
1
DROP TABLE t1;
1 mysql-test/suite/galera/t/galera_bf_background_statistics.opt
View file
@@ -0,0 +1 @@
--innodb_stats_persistent=ON
49 mysql-test/suite/galera/t/galera_bf_background_statistics.test
View file
@@ -0,0 +1,49 @@
--source include/galera_cluster.inc
--source include/have_innodb.inc

#
# Test a local transaction being aborted by a slave one while it is running a SLEEP()
#

SELECT @@innodb_stats_persistent;

CREATE TABLE t1 (f1 INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY, f2 INTEGER DEFAULT NULL) ENGINE=InnoDB;
INSERT INTO t1(f1) values (NULL);
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
INSERT INTO t1(f1) select NULL from t1;
SELECT count(1) from t1;

--connection node_2
SET AUTOCOMMIT=OFF;
--let $wsrep_local_bf_aborts_before = `SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_local_bf_aborts'`
INSERT INTO t1 VALUES (9999999,NULL);
--send SELECT SLEEP(1000);

--connection node_1
ALTER TABLE t1 CHANGE f2 f2 INTEGER NOT NULL DEFAULT 1;

--connection node_2
--error ER_LOCK_DEADLOCK
--reap

--let $wsrep_local_bf_aborts_after = `SELECT VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_local_bf_aborts'`

# Check that wsrep_local_bf_aborts has been incremented by exactly 1
--disable_query_log
--eval SELECT $wsrep_local_bf_aborts_after - $wsrep_local_bf_aborts_before = 1 AS wsrep_local_aborts_increment;
--enable_query_log

DROP TABLE t1;

25 storage/innobase/row/row0mysql.cc
View file
@@ -70,6 +70,13 @@ Created 9/17/2000 Heikki Tuuri
#include "ha_prototypes.h"
#include <algorithm>

#ifdef WITH_WSREP
#include "mysql/service_wsrep.h"
#include "wsrep.h"
#include "log.h"
#include "wsrep_mysqld.h"
#endif

/** Provide optional 4.x backwards compatibility for 5.0 and above */
UNIV_INTERN ibool row_rollback_on_timeout = FALSE;

@@ -1093,6 +1100,7 @@ UNIV_INLINE
void
row_update_statistics_if_needed(
/*============================*/
trx_t* trx,
dict_table_t* table) /*!< in: table */
{
ib_uint64_t counter;
@@ -1114,6 +1122,16 @@ row_update_statistics_if_needed(
if (counter > n_rows / 10 /* 10% */
&& dict_stats_auto_recalc_is_enabled(table)) {

#ifdef WITH_WSREP
if (wsrep_on(trx->mysql_thd) &&
wsrep_thd_is_BF(trx->mysql_thd, FALSE)) {
WSREP_DEBUG("Avoiding background statistics"
" calculation for table %s",
table->name);
return;
}
#endif /* WITH_WSREP */

dict_stats_recalc_pool_add(table);
table->stat_modified_counter = 0;
}
@@ -1537,7 +1555,8 @@ row_insert_for_mysql(
ut_memcpy(prebuilt->row_id, node->row_id_buf, DATA_ROW_ID_LEN);
}

row_update_statistics_if_needed(table);
row_update_statistics_if_needed(trx, table);

trx->op_info = "";

return(err);
@@ -1921,7 +1940,7 @@ row_update_for_mysql(
that changes indexed columns, UPDATEs that change only non-indexed
columns would not affect statistics. */
if (node->is_delete || !(node->cmpl_info & UPD_NODE_NO_ORD_CHANGE)) {
row_update_statistics_if_needed(prebuilt->table);
row_update_statistics_if_needed(trx, prebuilt->table);
} else {
/* Update the table modification counter even when
non-indexed columns change if statistics is initialized. */
@@ -2158,7 +2177,7 @@ row_update_cascade_for_mysql(
}
}

row_update_statistics_if_needed(table);
row_update_statistics_if_needed(trx, table);

return(err);
}

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