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Re: Optimizer for innodb does not reduce "data_free"
Posted by: Rick James
Date: December 08, 2012 01:33PM

* 4-7M is normal for "Free" on not-small InnoDB table. It won't go away.
* 4-7M does not mean "fragmentation"; it means space pre-allocated.
* Do not OPTIMIZE unless Free is a bigger percentage of the total.
* OPTIMIZE is rarely worth doing for InnoDB. The Data is always ordered by the PRIMARY KEY (unlike MyISAM); nothing will be 'rearranged' during OPTIMIZE.
* There is no good metric for degree of fragmentation. When Free is > 7M, then there is some fragmentation; however, there could be more space recoverable from Data, and maybe Index.

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Re: Optimizer for innodb does not reduce "data_free"
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