#
# Make sure pending LOCK TABLES doesn't block BACKUP STAGE
#
CREATE TABLE t1(a INT);
LOCK TABLE t1 READ;
#
connect con1,localhost,root,,;
SET DEBUG_SYNC= 'mdl_acquire_lock_wait SIGNAL ready' ;
LOCK TABLE t1 WRITE;
#
connect con2,localhost,root,,;
SET DEBUG_SYNC= 'now WAIT_FOR ready' ;
BACKUP STAGE START;
BACKUP STAGE FLUSH;
BACKUP STAGE BLOCK_DDL;
BACKUP STAGE END;
disconnect con2;
#
connection default;
UNLOCK TABLES;
#
connection con1;
UNLOCK TABLES;
disconnect con1;
#
connection default;
DROP TABLE t1;
SET DEBUG_SYNC= 'RESET' ;
#
# Demonstrates a deadlock if BACKUP namespace is reorder after SCHEMA.
# Culprit is ALTER TABLE taking SCHEMA lock on target database after
# BACKUP lock was acquired.
#
CREATE DATABASE test2;
CREATE TABLE t1(a INT) ENGINE=InnoDB;
connect con1,localhost,root,,;
BACKUP STAGE START;
connection default;
SET DEBUG_SYNC='alter_opened_table SIGNAL ready WAIT_FOR go' ;
ALTER TABLE t1 RENAME TO test2.t1;
connection con1;
SET DEBUG_SYNC='now WAIT_FOR ready' ;
SET DEBUG_SYNC='mdl_acquire_lock_wait SIGNAL ready1' ;
BACKUP STAGE BLOCK_DDL;
connect con2,localhost,root,,;
SET DEBUG_SYNC='now WAIT_FOR ready1' ;
SET DEBUG_SYNC='mdl_acquire_lock_wait SIGNAL go' ;
DROP DATABASE test2;
connection default;
connection con1;
disconnect con1;
connection con2;
disconnect con2;
connection default;
SET DEBUG_SYNC='reset' ;
Messung V0.5 in Prozent C=24 H=100 G=72
¤ Dauer der Verarbeitung: 0.11 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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