On 05/19/2010 06:14 AM, John Doe wrote: > From: Matt Keating<keatster at gmail.com> > >>> I don't usually use iozone (I usually use bonnie++) so take this with >>> a grain of salt, but those speed look suspiciously like cache speeds. >>> Bump the size (-s parameter) up to twice your real RAM size. >>> >> Will give that a try - 16gb file incoming >> > Or maybe do a: > sync; echo 3> /proc/sys/vm/drop_caches > between the 2 tests...? > It wouldn't help. The problem is the tests were using file sizes small enough to easily fit completely into the system caches. So you end up benchmarking the performance of the I/O system caches - not the drives themselves. -- Benjamin Franz