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MDEV-15641 InnoDB crash while committing table-rebuilding ALTER TABLE

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Problem:
========
 There is a possibility that there can be more concurrent DMLs While the
alter table thread is waiting for upgrading to MDL_EXCLUSIVE before commit phase.
In commit phase, InnoDB acquires dict_operation_lock and it already holds MDL_EXCLUSIVE
on the table. After that, InnoDB applies the concurrent DML logs in commit phase.
This could lead to blocking of the following things:

  1) DML on the particular table (due to MDL_EXCLUSIVE on the table)
  2) InnoDB DDLs (due to dict_operation_lock)
  3) Purge thread, stats thread, the master thread (due to dict_operation_lock)

Fix:
====
Apply the concurrent DML logs in commit phase but before acquiring
dict_operation_lock in commit phase. It makes sure that (2), (3) can't be
blocked for longer time.
This commit is contained in:
Thirunarayanan Balathandayuthapani
2019-07-10 12:37:48 +05:30
parent 578e822985
commit 64900e3d7c
5 changed files with 202 additions and 67 deletions
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49
mysql-test/suite/innodb/r/alter_large_dml.result Normal file
View File

@@ -0,0 +1,49 @@
CREATE TABLE t1(f1 char(200), f2 char(200), f3 char(200),
f4 char(200), f5 char(200), f6 char(200),
f7 char(200), f8 char(200))ENGINE=InnoDB;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
SET DEBUG_SYNC = 'inplace_after_index_build SIGNAL rebuilt WAIT_FOR dml_pause';
SET DEBUG_SYNC = 'alter_table_inplace_before_lock_upgrade SIGNAL dml_restart WAIT_FOR dml_done';
SET DEBUG_SYNC = 'row_log_table_apply2_before SIGNAL ddl_start';
ALTER TABLE t1 FORCE, ALGORITHM=INPLACE;
connect con1,localhost,root,,test;
SET DEBUG_SYNC = 'now WAIT_FOR rebuilt';
BEGIN;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
SET DEBUG_SYNC = 'now SIGNAL dml_pause';
SET DEBUG_SYNC = 'now WAIT_FOR dml_restart';
ROLLBACK;
BEGIN;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
INSERT INTO t1 SELECT '','','','','','','','' FROM seq_1_to_16384;
ROLLBACK;
BEGIN;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
ROLLBACK;
SET DEBUG_SYNC = 'now SIGNAL dml_done';
connect con2, localhost,root,,test;
SET DEBUG_SYNC = 'now WAIT_FOR ddl_start';
CREATE TABLE t2(f1 INT NOT NULL)ENGINE=InnoDB;
connection default;
SHOW CREATE TABLE t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` char(200) DEFAULT NULL,
`f2` char(200) DEFAULT NULL,
`f3` char(200) DEFAULT NULL,
`f4` char(200) DEFAULT NULL,
`f5` char(200) DEFAULT NULL,
`f6` char(200) DEFAULT NULL,
`f7` char(200) DEFAULT NULL,
`f8` char(200) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
SELECT COUNT(*) FROM t1;
COUNT(*)
16384
SET DEBUG_SYNC = 'RESET';
DROP TABLE t1, t2;