Mysql Deadlock debugging
Reported by Mike Perham | May 25th, 2008 @ 11:01 AM
Deadlocks and lock timeouts can be difficult to debug. This patch updates MysqlAdapter.execute to catch lock errors and print the results of SHOW INNODB STATUS which can help determine the problem.
You can pull the patch from:
http://github.com/mperham/rails/...
Commit c5582f0b82f842af712ae8b9a5efc713bbd736c3
A unit test is included.
Comments and changes to this ticket
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Jeremy Kemper May 25th, 2008 @ 03:38 PM
This command is only available to mysql superusers so log_innodb_status should check for errors.
Also, could you attach a patch created with git-format-patch? It's much simpler than adding a remote, fetching, cherrypicking a single commit, etc.
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Mike Perham May 25th, 2008 @ 05:19 PM
Jeremy, sorry I'm not terribly git-fluent. I've pushed a new commit with the error handling you requested to my fork but I don't know the exact patch command to do what you want. tim pope's "how to contribute to rails with git" page doesn't help either. Can you send me the command to emit a patch for a given commit? This prints out nothing:
git format-patch cb6aa8e8516cef55b81f6a061a3e87c6208cd553
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Jeremy Kemper May 25th, 2008 @ 05:25 PM
Thanks Mike! Check out http://rails.lighthouseapp.com/p... for the skinny.
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Mike Perham May 25th, 2008 @ 08:22 PM
One thing I forgot, the log_innodb_status method should be moved down to the private section.
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Joshua Peek July 16th, 2008 @ 07:56 PM
- → Assigned user changed from “” to “Jeremy Kemper”
- → Tag changed from “” to “activerecord patch”
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Source available from github
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Adam Keys