On Mon, 12 Aug 2013 11:01:09 -0500 (CDT) Scott Whitney <scott@xxxxxxxxxxx> wrote: > When you say "16 10K drives," do you mean: I mean 8 RAID-1 pairs with data striped across the pairs. The Linux software RAID "offset" scheme is described here: http://www.ilsistemista.net/index.php/linux-a-unix/35-linux-software-raid-10-layouts-performance-near-far-and-offset-benchmark-analysis.html?start=1 > The SSD solution I put in has shown significant speed improvements, > to say the very least. OK; thanks. > Basically, just assume that you're getting 130 iops per drive. Well, > 16 drives in a RAID 0 is going to max you out at 2100ish iops, With our RAID-10 array, we're looking at about 1050 iops. Our server currently is holding up OK with a decidedly non-optimal arrangment (four RAID-1 volumes with pg_xlog on one, most DB files on a second, and a couple of tablespaces with hand-placed tables and indexes on the other two, and only 7200 RPM disks.) So I think 16 10Krpm spinning disks will probably suffice; the failure mode of SSDs makes me nervous. Regards, David. -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
