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|
--echo #
--echo # Bug #21278148 DEADLOCKS MISSED BY INFORMATION_SCHEMA.INNODB_METRICS
--echo # LOCK_DEADLOCKS COUNTER
--echo #
--source include/have_debug_sync.inc
CREATE TABLE t(a INT PRIMARY KEY, b INT) ENGINE=InnoDB;
INSERT INTO t VALUES (2,1), (1,2);
--echo # Scenario 1: the con1 will be chosen as victim
SELECT `count` INTO @deadlocks_before_test
FROM INFORMATION_SCHEMA.INNODB_METRICS
WHERE NAME="lock_deadlocks";
--connect (con1,localhost,root,,)
BEGIN;
SELECT b FROM t WHERE a=1 FOR UPDATE;
--connect (con2,localhost,root,,)
BEGIN;
# Make con2 "heavy" by creating new rows
INSERT INTO t VALUES (3,3), (4,4), (5,5);
SELECT b FROM t WHERE a=2 FOR UPDATE;
--connection con1
SET DEBUG_SYNC='lock_wait_will_wait SIGNAL con1_will_wait';
--send SELECT b FROM t WHERE a=2 FOR UPDATE;
--connection con2
SET DEBUG_SYNC='now WAIT_FOR con1_will_wait';
SELECT b FROM t WHERE a=1 FOR UPDATE;
ROLLBACK;
--connection con1
--error ER_LOCK_DEADLOCK
--reap
--connection default
--disconnect con1
--disconnect con2
SELECT `count` - @deadlocks_before_test AS deadlocks_during_test
FROM INFORMATION_SCHEMA.INNODB_METRICS
WHERE NAME="lock_deadlocks";
--echo # Scenario 2: the con2 will be chosen as victim
SELECT `count` INTO @deadlocks_before_test
FROM INFORMATION_SCHEMA.INNODB_METRICS
WHERE NAME="lock_deadlocks";
--connect (con1,localhost,root,,)
BEGIN;
SELECT b FROM t WHERE a=1 FOR UPDATE;
--connect (con2,localhost,root,,)
BEGIN;
SELECT b FROM t WHERE a=2 FOR UPDATE;
--connection con1
SET DEBUG_SYNC='lock_wait_will_wait SIGNAL con1_will_wait';
--send SELECT b FROM t WHERE a=2 FOR UPDATE;
--connection con2
SET DEBUG_SYNC='now WAIT_FOR con1_will_wait';
--error ER_LOCK_DEADLOCK
SELECT b FROM t WHERE a=1 FOR UPDATE;
--connection con1
--reap
ROLLBACK;
--connection default
--disconnect con1
--disconnect con2
SELECT `count` - @deadlocks_before_test AS deadlocks_during_test
FROM INFORMATION_SCHEMA.INNODB_METRICS
WHERE NAME="lock_deadlocks";
DROP TABLE t;
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