On Tuesday 01 May 2007 08:28, Feizhou wrote: > > 3.) Use the deadline I/O scheduler, anticipatory and XFS don't like each > > other. This is true for almost any FS != ext3. This makes a difference > > especially for OLTP. > > Default on Centos 5 should be neither. It is CFQ IIRC. Here's a quick (if slightly older) writeup of CFQ, which mentions some code was borrowed from the Anticipatory Scheduler. http://lwn.net/Articles/114770/ And here's a post from what seems to be the developer stating it explicitly. http://lwn.net/Articles/114773/ I have no idea whether the shared code contains the portions that XFS finds fault with. -- - Kevan Benson - A-1 Networks