mirror of
https://github.com/MariaDB/server.git
synced 2025-07-27 13:45:12 +02:00
13b9ec651a
When the transaction isolation level is SERIALIZABLE, or when a locking read is performed in the REPEATABLE READ isolation level, InnoDB must lock delete-marked records in order to prevent another transaction from inserting something. However, at READ UNCOMMITTED or READ COMMITTED isolation level or when the parameter innodb_locks_unsafe_for_binlog is set, the repeatability of the reads does not matter, and there is no need to lock any records. row_search_mvcc(): Skip locks on delete-marked committed records upfront, instead of invoking row_unlock_for_mysql() afterwards. The unlocking never worked for secondary index records.
72 lines
1.5 KiB
Text
72 lines
1.5 KiB
Text
--source include/have_innodb.inc
|
|
--source include/have_debug.inc
|
|
--source include/have_debug_sync.inc
|
|
|
|
--source include/count_sessions.inc
|
|
|
|
connect(stop_purge, localhost, root,,);
|
|
START TRANSACTION WITH CONSISTENT SNAPSHOT;
|
|
connect(delete, localhost, root,,);
|
|
connection default;
|
|
|
|
CREATE TABLE t1(a INT PRIMARY KEY, b INT UNIQUE) ENGINE=InnoDB;
|
|
INSERT INTO t1 VALUES(1,1);
|
|
DELETE FROM t1;
|
|
|
|
let $i=2;
|
|
while ($i) {
|
|
let $iso= `SELECT CASE $i WHEN 1 THEN 'UNCOMMITTED' ELSE 'COMMITTED' END`;
|
|
|
|
SET DEBUG_SYNC='row_ins_sec_index_unique SIGNAL inserted WAIT_FOR locked';
|
|
BEGIN;
|
|
send INSERT INTO t1 VALUES(1,1);
|
|
|
|
connection delete;
|
|
SET DEBUG_SYNC='now WAIT_FOR inserted';
|
|
SET DEBUG_SYNC='innodb_row_search_for_mysql_exit SIGNAL locked';
|
|
eval SET SESSION TRANSACTION ISOLATION LEVEL READ $iso;
|
|
BEGIN;
|
|
send DELETE FROM t1 WHERE b=1;
|
|
|
|
connection default;
|
|
reap;
|
|
connection delete;
|
|
reap;
|
|
COMMIT;
|
|
|
|
connection default;
|
|
SET DEBUG_SYNC='RESET';
|
|
ROLLBACK;
|
|
|
|
dec $i;
|
|
}
|
|
|
|
SET DEBUG_SYNC='row_ins_sec_index_unique SIGNAL inserted WAIT_FOR locked';
|
|
BEGIN;
|
|
SET innodb_lock_wait_timeout=1;
|
|
send INSERT INTO t1 VALUES(1,1);
|
|
|
|
connection delete;
|
|
SET DEBUG_SYNC='now WAIT_FOR inserted';
|
|
SET DEBUG_SYNC='innodb_row_search_for_mysql_exit SIGNAL locked';
|
|
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
|
|
BEGIN;
|
|
send DELETE FROM t1 WHERE b=1;
|
|
|
|
connection default;
|
|
--error ER_LOCK_WAIT_TIMEOUT
|
|
reap;
|
|
COMMIT;
|
|
SET DEBUG_SYNC='RESET';
|
|
|
|
connection delete;
|
|
reap;
|
|
COMMIT;
|
|
|
|
disconnect delete;
|
|
disconnect stop_purge;
|
|
|
|
connection default;
|
|
DROP TABLE t1;
|
|
|
|
--source include/wait_until_count_sessions.inc
|