On Tue, 26 May 2009, Scott Marlowe wrote:
Plus if you only need 4 drives or something, you can do pretty well with a Dell with the RAID controller turned to JBOD and letting the linux kernel do the RAID work.
I think most of the apps I'm considering would be OK with 4 drives and a useful write cache. The usual hosted configurations are only 1 or 2 and no usable cache, which really limits what you can do with the server before you run into a disk bottleneck. My rule of thumb is that any single core will be satisfied as long as you've got at least 4 disks to feed it, since it's hard for one process to use more than a couple of hundred MB/s for doing mostly sequential work. Obviously random access is much easier to get disk-bound, where you have to throw a lot more disks at it.
It wouldn't surprise me to find it's impossible to get an optimal setup of 8+ disks from any hosting provider. Wasn't asking for "great" DB performance though, just "good".
-- * Greg Smith gsmith@xxxxxxxxxxxxx http://www.gregsmith.com Baltimore, MD -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
