On 4/2/13, John R Pierce <pierce@xxxxxxxxxxxx> wrote: > On 4/2/2013 3:35 PM, David Noel wrote: >> The hardware is a Dell PowerEdge 1420, dual Xeon Nocona's, 3.2ghz, >> 16gb ram. The disks are 4 Kingston HyperX SATA3's attached to a >> HighPoint RocketRAID 2721 controller, ZFS, RAID10. > ..... >> postgresql.conf, all standard/default except for: >> max_connections = 256 > > A) use a connection pool so you don't NEED 256 active database connections. > > B) shared_buffers, work_mem, and maintenance_work_mem all need to be > tuned. I'd suggest 4gb, 16mb, 1gb respectively as a starting point on > a 16GB ram system. if you can, shrink your max_connections by using a > connection pooler (my target is generally no more than 2-4 active > queries per CPU core or hardware thread). Ouch, Xeon Nocona was a > single core, dual thread CPU, with rather poor performance, essentially > just a Pentium-4... 3Ghz on a P4 is like 2Ghz on other CPUs. > > when you said raid10, do you mean zfs mirrored, or are you doing > hardware raid10 in the Highpoint? I would have configured the raid > card for JBOD, and done ZFS mirroring in the OS, so you can take > advantage of ZFS's data integrity features. Those are consumer > grade SSD's, are they even qualified for use with that Highpoint > controller ? > > > -- > john r pierce 37N 122W > somewhere on the middle of the left coast It looks like you guys were spot on, thanks. I've incorporated some of the suggested values, done a little RTFM'ing (chapter 18.4), made a few additional tweaks, and have brought things to a seemingly stable state. Still testing, but so far so good. Glad it was such a simple "fix". Many thanks, -David -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
