ActiveRecord::StatementInvalid: Mysql2::Error: Lost connection to MySQL server during query: SHOW TABLES LIKE 'users'

[mohitnegi]

I'm using mysql2 0.3.13, rails 3.2.14, ruby 1.9.3p448 (2013-06-27 revision 41675) [x86_64-linux] .. and I'm getting this problem intermittently on production. Any suggestions? My wait_timeout in mysql is set to 28800.

[sodabrew]

What was the previous query? Your connection may have timed out before starting this query. Any other timeout values that are set low? Is reconnect enabled or disabled?

[brianmario]

Sounds related to http://bugs.mysql.com/bug.php?id=65956

[WilliamDenniss]

By any chance have you set the reaping_frequency ActiveRecord config? I found that the ActiveRecord connection reaper was causing this error. It's disabled by default in rails (for good reason it seems), but some some samples out there recommend enabling it (such as from Heroku).

See this issue from Rails rails/rails#9907 and my SO answer on this topic: http://stackoverflow.com/a/22423893/72176

[sodabrew]

Closing per @WilliamDenniss blog post explaining the bad news reaping_frequency option. And lack of updates.