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Re: At Performance Limit for 2 GB RAM?
Posted by: KimSeong Loh
Date: July 26, 2005 06:55PM

Difference between MyISAM and InnoDB
- MyISAM rows is stored in random in the data file, InnoDB has a clusted index on the Primary Key.
This could make some differences in the number of required disk acess.

Since the query is using the Primay key index, InnoDB may have read multiple rows in the same page/block, so it is likely that the next row that is required is already in the memory.
MyISAM needs to read 1 row at a time, each one is likely to require a disk access since the rows are not ordered in any way.

Maybe you can post the EXPLAIN result as well, it can probably show something that can give a better description of what is happening.

Also, the various buffer size allocated to MyISAM and InnoDB may also play a role.

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Written By
Re: At Performance Limit for 2 GB RAM?
July 26, 2005 06:55PM
August 04, 2005 07:17PM

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