Open table cache in MySQL

Posted by vvanscherpenseel on Server Fault See other posts from Server Fault or by vvanscherpenseel
Published on 2012-10-19T14:52:47Z Indexed on 2013/10/21 9:59 UTC
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mysql

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cache

I have my open table cache set to 1800 and I have a total of 1112 tables. MySQL Tuning Primer reports that 100% of my table cache is used yet my table cache hit rate is 5%. I understand that this happens due to concurrent connections all opening tables. I think I should raise the cache limit. I understand that the cache size is limited by the file descriptor limit of my operating system, but are there any other practical limitations I should be aware of?

Searching Google or this very website yields mostly posts explaining the connection-factor or come up with indecisive answers.

My question: can I safely increase the open table cache limit? Is there a maximum?

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