From 17a6040fbcaf1610ccd4d69fe3849a6fcb3d71a8 Mon Sep 17 00:00:00 2001 From: Jon Olav Hauglid Date: Wed, 4 Nov 2009 12:59:46 +0100 Subject: Bug #43867 ALTER TABLE on a partitioned table causes unnecessary deadlocks Backport of revno: 2617.68.35 The problem was that if one connection is running a multi-statement transaction which involves a single partitioned table, and another connection attempts to alter the table to drop a non-existing partition, (which of course will fail), the first connection still gets ER_LOCK_DEADLOCK and cannot proceed anymore. This bug is no longer reproducable. This has also been tested with the patch for Bug#46654 "False deadlock on concurrent DML/DDL with partitions, inconsistent behavior" which concerned a similar problem but where the ALTER TABLE is semantically correct. Test case added in partition_sync.test. --- mysql-test/r/partition_sync.result | 25 +++++++++++++++++++++++ mysql-test/t/partition_sync.test | 41 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+) create mode 100644 mysql-test/r/partition_sync.result create mode 100644 mysql-test/t/partition_sync.test diff --git a/mysql-test/r/partition_sync.result b/mysql-test/r/partition_sync.result new file mode 100644 index 00000000000..31cf0569464 --- /dev/null +++ b/mysql-test/r/partition_sync.result @@ -0,0 +1,25 @@ +# +# Bug #43867 ALTER TABLE on a partitioned table +# causes unnecessary deadlocks +# +CREATE TABLE t1 (a int) PARTITION BY RANGE (a) +(PARTITION p0 VALUES LESS THAN (1), +PARTITION p1 VALUES LESS THAN (2)); +INSERT INTO t1 VALUES (0),(1); +# Connection 2 +BEGIN; +SELECT * FROM t1; +a +0 +1 +# Connection 1 +ALTER TABLE t1 DROP PARTITION p3; +ERROR HY000: Error in list of partitions to DROP +# Connection 2 +# This failed with deadlock and should not do so. +SELECT * FROM t1; +a +0 +1 +# Connection 1 +DROP TABLE t1; diff --git a/mysql-test/t/partition_sync.test b/mysql-test/t/partition_sync.test new file mode 100644 index 00000000000..a732b35b8b9 --- /dev/null +++ b/mysql-test/t/partition_sync.test @@ -0,0 +1,41 @@ +--source include/have_partition.inc +# Save the initial number of concurrent sessions. +--source include/count_sessions.inc + +--echo # +--echo # Bug #43867 ALTER TABLE on a partitioned table +--echo # causes unnecessary deadlocks +--echo # + +CREATE TABLE t1 (a int) PARTITION BY RANGE (a) +(PARTITION p0 VALUES LESS THAN (1), + PARTITION p1 VALUES LESS THAN (2)); + +INSERT INTO t1 VALUES (0),(1); + +connect(con1,localhost,root); + +--echo # Connection 2 +connection con1; +BEGIN; +SELECT * FROM t1; + +--echo # Connection 1 +connection default; +--error ER_DROP_PARTITION_NON_EXISTENT +ALTER TABLE t1 DROP PARTITION p3; + +--echo # Connection 2 +connection con1; +--echo # This failed with deadlock and should not do so. +SELECT * FROM t1; + +--echo # Connection 1 +connection default; +disconnect con1; +DROP TABLE t1; + + +# Check that all connections opened by test cases in this file are really +# gone so execution of other tests won't be affected by their presence. +--source include/wait_until_count_sessions.inc -- cgit v1.2.1