On Tue, Mar 2, 2010 at 2:30 PM, Francisco Reyes <lists@xxxxxxxxxxxxxxxx> wrote: > Scott Marlowe writes: > >> Then the real thing to compare is the speed of the drives for >> throughput not rpm. > > In a machine, simmilar to what I plan to buy, already in house 24 x 10K rpm > gives me about 400MB/sec while 16 x 15K rpm (2 to 3 year old drives) gives > me about 500MB/sec Have you tried short stroking the drives to see how they compare then? Or is the reduced primary storage not a valid path here? While 16x15k older drives doing 500Meg seems only a little slow, the 24x10k drives getting only 400MB/s seems way slow. I'd expect a RAID-10 of those to read at somewhere in or just past the gig per second range with a fast pcie (x8 or x16 or so) controller. You may find that a faster controller with only 8 or so fast and large SATA drives equals the 24 10k drives you're looking at now. I can write at about 300 to 350 Megs a second on a slower Areca 12xx series controller and 8 2TB Western Digital Green drives, which aren't even made for speed. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
