Re: performance config help

On Mon, Jan 11, 2010 at 6:44 AM, Bob Dusek <redusek@gmail.com> wrote:
> Hello,
>
> We're running Postgres 8.4.2 on Red Hat 5, on pretty hefty hardware...
>
> 4X E7420 Xeon, Four cores (for a total of 16 cores)
> 2.13 GHz, 8M Cache, 1066 Mhz FSB
> 32 Gigs of RAM
> 15 K RPM drives in striped raid

What method of striped RAID?  RAID-5?  RAID-10?  RAID-4?  RAID-0?

> Things run fine, but when we get a lot of concurrent queries running, we see
> a pretty good slow down.

Definte "a lot".

> We don't have much experience with this sort of hardware.   Does anyone have
> an example config file we could use as a good starting point for this sort
> of hardware?
>
> We have a fair amount of row-level inserts and deletes going on (probably as
> much data is inserted and deleted in a day than permanently resides in the
> db).

What do the following commands tell you?

iostat -x 10 (first iteration doesn't count)
vmstat 10 (again, first iteration doesn't count)
top

What you're looking for is iowait / utilization.