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37 lines
985 B
Text
37 lines
985 B
Text
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# MDEV-20946 Hard FTWRL deadlock under user level locks
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#
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# Deadlock detector should resolve conflicts between FTWRL and user locks.
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--source include/have_debug_sync.inc
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--source include/count_sessions.inc
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CREATE TABLE t1(a INT);
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SELECT GET_LOCK("l1", 0);
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connect(con1,localhost,root,,);
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LOCK TABLES t1 WRITE;
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connection default;
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set debug_sync='mdl_acquire_lock_wait SIGNAL ftwrl';
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send FLUSH TABLES WITH READ LOCK;
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# At this point "default" is waiting for tables to be unlocked from
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# LOCK TABLES WRITE issued by "con1".
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connection con1;
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set debug_sync='now WAIT_FOR ftwrl';
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# The lock in the following GET_LOCK cannot be acquired since "default" holds
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# a lock on "l1" and is waiting in FLUSH TABLES for con1.
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--error ER_LOCK_DEADLOCK
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SELECT GET_LOCK("l1", 1000);
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disconnect con1; # Performs an implicit UNLOCK TABLES.
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connection default;
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reap;
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SELECT RELEASE_LOCK("l1");
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UNLOCK TABLES;
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DROP TABLE t1;
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set debug_sync='reset';
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--source include/wait_until_count_sessions.inc
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