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Re: Recent Upgrade from MySQL 5.1 to 5.5
Posted by: Rick James
Date: December 12, 2016 02:08PM

One setting that can cause a performance degradation is query_cache_size. The bigger it is, the more time is spent pruning the QC.

Please provide these; I will dig deaper:
SHOW VARIABLES;
SHOW GLOBAL STATUS;

In general, hardware is not the way to improve MySQL. And rarely is tuning that useful (at least after getting a few things right). If you are having performance, problems, set long_query_time=1, turn on the slowlog, wait a day, then use one of these on the slowlog file:
mysqldumpslow -s t
pt-query-digest
Then come here for help in the first few queries.

In the long run, you must go to InnoDB and 5.7 -- each of those is _probably_ more useful than the hardware upgrade you did.

What filesystem (xfs, zfs, ext3, etc) is on the old/new machines?

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Re: Recent Upgrade from MySQL 5.1 to 5.5
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