MySQL Bugs: #37990: Select on IS failed (Was: main.backup_commit

Bug #37990	Select on IS failed (Was: main.backup_commit_blocker hangs)
Submitted:	9 Jul 2008 13:31	Modified:	26 Mar 2009 23:29
Reporter:	Chuck Bell	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Information schema	Severity:	S3 (Non-critical)
Version:	6.0.6, 6.0-backup bzr	OS:	Any
Assigned to:	Chuck Bell	CPU Architecture:	Any
Tags:	pushbuild, sporadic, test failure

Description:
The backup_commit_blocker test can hang randomly on the SELECT ... FROM INFORMATION_SCHEMA.PROCESSLIST commands.

These commands shall be commented out until this problem can be fixed.

Note: It is likely that other tests that use this method could hang, but this is the only test that does so.

How to repeat:
MTR on mysql-6.0-backup tree.

Suggested fix:
N/A

A patch for this bug can be found here: <http://lists.mysql.com/commits/49309>

An initial patch was created to disable the SELECTs for INFORMATION_SCHEMA.PROCESSLIST. It was approved by Chuck and Ingo.

http://lists.mysql.com/commits/49309

Bug remains open for verification and schedule to fix.

Bug #39176 can be related.

Thank you for the report.

Verified as described using mysql-6.0-backup tree and running test >10 times

I cannot repeat this failure. It was present only once in PB and not since.

oops. Please disregard last post -- I updated the wrong bug report.

The backup_ddl_blocker.test has these selects in it. They should be removed by work for WL#4644.

The backup test has one select in it. I think it can be removed.

See line#117:

--replace_column 1 #
query_vertical SELECT id, command, state, info FROM INFORMATION_SCHEMA.PROCESSLIST
WHERE info LIKE "BACKUP DATABASE%" OR state LIKE "%holding table locks%";

Conclusion
----------
Once the backup test has been changed and WL#4644 is complete, this bug report can be closed.

The following tests have the offending select and must be modified:

backup.backup
backup.backup_ddl_blocker (to be fixed by WL#4644 so not part of this fix)
backup.backup_lock_myisam
backup.backup_logs

The backup_logs test is ok and does not need modification.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/65055

2757 Chuck Bell	2009-02-03
      BUG#37990 Select on IS failed (Was: main.backup_commit_blocker hangs) 
      
      The select from information_schema.processlist is unreliable. It must
      be removed from all backup tests. This patch does that for the backup
      and backup_lock_myisam test.

Good to push.

Patch approved. Good to push

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/65374

2760 Chuck Bell	2009-02-05
      BUG#37990 Select on IS failed (Was: main.backup_commit_blocker hangs) 
      
      The select from information_schema.processlist is unreliable. It must
      be removed from all backup tests. This patch does that for the backup
      and backup_lock_myisam test.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/70145

2792 Rafal Somla	2009-03-23
      Remove SELECTs from I_S.PROCESSLIST from tests, because such selects are unstable
      in the current server (see bug#37990, bug#41346, bug#43357). These selects increase
      feedback given by test and thus increases chances of detecting problems, but are
      not essential for test purposes.
     @ mysql-test/suite/backup/include/bml_test.inc
        Comment-out SELECTs from I_S.PROCESSLIST.
     @ mysql-test/suite/backup/t/backup_bml.test
        Comment-out SELECTs from I_S.PROCESSLIST.
     @ mysql-test/suite/backup_engines/include/backup_restore_interrupt.inc
        Comment-out SELECTs from I_S.PROCESSLIST.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/70165

2793 Rafal Somla	2009-03-23
      Remove SELECTs from I_S.PROCESSLIST from tests, because such selects are unstable
      in the current server (see bug#37990, bug#41346, bug#43357). These selects increase
      feedback given by test and thus increases chances of detecting problems, but are
      not essential for test purposes.
     @ mysql-test/suite/backup/include/bml_test.inc
        Comment-out SELECTs from I_S.PROCESSLIST.
     @ mysql-test/suite/backup/t/backup_bml.test
        Comment-out SELECTs from I_S.PROCESSLIST.
     @ mysql-test/suite/backup_engines/include/backup_restore_interrupt.inc
        Comment-out SELECTs from I_S.PROCESSLIST.

Pushed into 6.0.11-alpha (revid:alik@sun.com-20090326121822-pt84kzxxayzho4mn) (version source revid:rafal.somla@sun.com-20090206175321-gekdgu0f60n6oh9p) (merge vers: 6.0.10-alpha) (pib:6)

Test case changes. No changelog entry needed.

Pushed into 6.0.11-alpha (revid:alik@sun.com-20090423070920-e5lq3vrrqi016z2c) (version source revid:alik@sun.com-20090423070920-e5lq3vrrqi016z2c) (merge vers: 6.0.11-alpha) (pib:6)