CREATE TABLE t1 (f1 INT PRIMARY KEY) ENGINE=InnoDB;
# Case1: Server goes through graceful shutdown and is restarted
connection default;
INSERT INTO t1 VALUES (1);
Performing --wsrep-recover ...
Using --wsrep-start-position when starting mysqld ...
Expect 100-10-2
SELECT WSREP_LAST_SEEN_GTID();
WSREP_LAST_SEEN_GTID() 100-10-2
SELECT @@GLOBAL.gtid_binlog_pos;
@@GLOBAL.gtid_binlog_pos 100-10-2
SELECT * FROM t1;
f1 1
# Case2: Server is killed after the transaction gets prepared
# but before it is written into binlog. As there is not GTID assigned,
# the transaction must be rolled back during recovery.
connect con, localhost, root; SET DEBUG_SYNC = "ha_commit_trans_after_prepare SIGNAL reached WAIT_FOR continue";
INSERT INTO t1 VALUES (2);
connection default; SET DEBUG_SYNC = "now WAIT_FOR reached";
# Kill the server
Performing --wsrep-recover ...
Using --wsrep-start-position when starting mysqld ...
Expect 100-10-2
SELECT WSREP_LAST_SEEN_GTID();
WSREP_LAST_SEEN_GTID() 100-10-2
SELECT @@GLOBAL.gtid_binlog_pos;
@@GLOBAL.gtid_binlog_pos 100-10-2
Expect 1
SELECT * FROM t1;
f1 1
disconnect con;
# Case3: Server is killed after the transaction gets written into binlog
# but before it is committed in storage engine. In this case the
# transaction must be committed during recovery as it had a valid
# GTID assigned.
connect con, localhost, root; SET DEBUG_SYNC = "commit_before_get_LOCK_commit_ordered SIGNAL reached WAIT_FOR continue";
INSERT INTO t1 VALUES (3);
connection default; SET DEBUG_SYNC = "now WAIT_FOR reached";
# Kill the server
Performing --wsrep-recover ...
Using --wsrep-start-position when starting mysqld ...
Expect 100-10-3
SELECT WSREP_LAST_SEEN_GTID();
WSREP_LAST_SEEN_GTID() 100-10-3
SELECT @@GLOBAL.gtid_binlog_pos;
@@GLOBAL.gtid_binlog_pos 100-10-3
Expect 13
SELECT * FROM t1;
f1 1 3
disconnect con;
DROP TABLE t1;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.8 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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