make stat computations sane

[hermanlee]

Issue by maykov
Wednesday Aug 19, 2015 at 17:01 GMT
Originally opened as MySQLOnRocksDB#97

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Right now, there is a delay of 1 hour between stat computes when using default options. This makes MyRocks fail (run slow) on standard tests such as Wisconsin. We need to fix this.

E.g.: i.e. updating stats on table X (including Memstore) if all of the indexes of the table are less than Y bytes, whenever the table was accessed.

[yoshinorim]

https://reviews.facebook.net/D48495 resolved this issue.