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  • Arshan Qureshi thinks this is interesting:

MyISAM in the way the table data is cached. MyISAM caches only the keys, and simply hopes the OS will do a good job caching the data. InnoDB does not put any faith in the OS and takes the matter of caching the data into its own hands.

From

Cover of Understanding MySQL Internals

Note

Difference between MyISAM and InnoDB