mariadb/mysql-test/suite/innodb/t/deadlock_detect.test
Marko Mäkelä ddd7d5d8e3 MDEV-24035 Failing assertion: UT_LIST_GET_LEN(lock.trx_locks) == 0 causing disruption and replication failure
Under unknown circumstances, the SQL layer may wrongly disregard an
invocation of thd_mark_transaction_to_rollback() when an InnoDB
transaction had been aborted (rolled back) due to one of the following errors:
* HA_ERR_LOCK_DEADLOCK
* HA_ERR_RECORD_CHANGED (if innodb_snapshot_isolation=ON)
* HA_ERR_LOCK_WAIT_TIMEOUT (if innodb_rollback_on_timeout=ON)

Such an error used to cause a crash of InnoDB during transaction commit.
These changes aim to catch and report the error earlier, so that not only
this crash can be avoided but also the original root cause be found and
fixed more easily later.

The idea of this fix is from Michael 'Monty' Widenius.

HA_ERR_ROLLBACK: A new error code that will be translated into
ER_ROLLBACK_ONLY, signalling that the current transaction
has been aborted and the only allowed action is ROLLBACK.

trx_t::state: Add TRX_STATE_ABORTED that is like
TRX_STATE_NOT_STARTED, but noting that the transaction had been
rolled back and aborted.

trx_t::is_started(): Replaces trx_is_started().

ha_innobase: Check the transaction state in various places.
Simplify the logic around SAVEPOINT.

ha_innobase::is_valid_trx(): Replaces ha_innobase::is_read_only().

The InnoDB logic around transaction savepoints, commit, and rollback
was unnecessarily complex and might have contributed to this
inconsistency. So, we are simplifying that logic as well.

trx_savept_t: Replace with const undo_no_t*. When we rollback to
a savepoint, all we need to know is the number of undo log records
that must survive.

trx_named_savept_t, DB_NO_SAVEPOINT: Remove. We can store undo_no_t
directly in the space allocated at innobase_hton->savepoint_offset.

fts_trx_create(): Do not copy previous savepoints.

fts_savepoint_rollback(): If a savepoint was not found, roll back
everything after the default savepoint of fts_trx_create().
The test innodb_fts.savepoint is extended to cover this code.

Reviewed by: Vladislav Lesin
Tested by: Matthias Leich
2024-12-12 18:02:00 +02:00

100 lines
2.4 KiB
Text

#
# wl#9383 INNODB: ADD AN OPTION TO TURN OFF/ON DEADLOCK CHECKER
#
--source include/have_innodb.inc
--source include/count_sessions.inc
--disable_query_log
call mtr.add_suppression("InnoDB: Transaction was aborted due to ");
--enable_query_log
let $have_deadlock=`select @@GLOBAL.innodb_deadlock_detect`;
connection default;
CREATE TABLE t1(
id INT,
PRIMARY KEY(id)
) ENGINE=InnoDB;
CREATE TABLE dl(
id INT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
cnt INT UNSIGNED
) ENGINE=InnoDB;
INSERT INTO t1 VALUES(1), (2), (3);
# Preserve the initial value of the deadlock counter
INSERT INTO dl(cnt) SELECT variable_value FROM information_schema.global_status WHERE variable_name LIKE 'Innodb_deadlocks';
# We are not interested query results, only errors
--disable_result_log
BEGIN;
SELECT * FROM t1 WHERE id = 1 LOCK IN SHARE MODE;
connect (con1,localhost,root,,);
BEGIN;
SELECT * FROM t1 WHERE id = 2 LOCK IN SHARE MODE;
connect (con2,localhost,root,,);
BEGIN;
SELECT * FROM t1 WHERE id = 2 LOCK IN SHARE MODE;
send SELECT * FROM t1 WHERE id = 1 FOR UPDATE;
connection default;
send SELECT * FROM t1 WHERE id = 2 FOR UPDATE;
connection con2;
if (!$have_deadlock) {
--error ER_LOCK_WAIT_TIMEOUT
reap;
disconnect con1;
}
if ($have_deadlock) {
connection con1;
COMMIT;
disconnect con1;
connection con2;
--error 0,ER_LOCK_DEADLOCK,ER_LOCK_WAIT_TIMEOUT
reap;
}
ROLLBACK;
disconnect con2;
#
# Note here that con1 is the older transaction as it
# query started wait first. Thus, con1 gets lock
# wait timeout first. There is possibility that
# default connection gets lock timeout also or
# as con1 is rolled back it gets the locks it waited
# and does the update.
#
connection default;
--let $valid_deadlock_cnt= 1
if (!$have_deadlock) {
--error 0,ER_LOCK_WAIT_TIMEOUT
reap;
}
if ($have_deadlock) {
--error 0,ER_LOCK_DEADLOCK
reap;
--disable_query_log
INSERT INTO dl(cnt) SELECT variable_value FROM information_schema.global_status WHERE variable_name LIKE 'Innodb_deadlocks';
set @init_deadlock_cnt = (SELECT min(k.cnt) FROM dl k);
--let $valid_deadlock_cnt= `SELECT (max(t.cnt-@init_deadlock_cnt) = 1) FROM dl t`
--enable_query_log
}
# Indicates that the deadlock counter works well.
# Use the default =1 where is no deadlock detection,
# to enable unconditional check.
--echo 'Deadlock counter is valid';
--echo $valid_deadlock_cnt
ROLLBACK;
--enable_result_log
DROP TABLE t1;
DROP TABLE dl;
--source include/wait_until_count_sessions.inc