Sure, there are tools and script to help you fine tune your MySQL server but there’s nothing like using your brain.
Pythian has done a wonderful job of explaining what all those InnoDb-related variables in a series of articles…
Exposing Innodb Internals via System Variables:
Part 1, Memory
Exposing Innodb Internals via System Variables:
Part 2, I/O (structure and logs)
Exposing Innodb Internals via System Variables:
Part 3, I/O (Table data)
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