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Message: <blockquote data-quote="nerfherder" data-source="post: 3010647" data-attributes="member: 18305">If you are searching for all data and then ordering it by date, so you may be doing a table scan.  I believe you have a pair of disks in a RAID 1 configuration (i.e. mirrored) so that will hit one of the disks hard.  This may then be followed by a sort on disk (if a lot of data is retrieved), this time hitting both disks hard.  During a table scan, other queries will be able to use the other disk, but during a disk sort both disks will be being written to, slowing other queries dramatically.You might want to do EXPLAIN on the SQL to get the query execution plan to see whether it is using any indexes (especially on date - you ideally want to be able to just retrieve the most recent n number, not all of them), and whether it is doing filesort (i.e. sorting on disk).There's a bit more info here: <a href="http://mysql.com/doc/refman/5.1/en/order-by-optimization.html" target="_blank">http://mysql.com/doc/refman/5.1/en/order-by-optimization.html</a>Cheers,LiamP.S. feel free to send me the SQL, table and index definitions and SQL EXPLAIN output by email to nerfherder67 at hotmail dot com.  I'm more an Oracle expert, but I'm sure MySQL can't be too different.</blockquote>