Re: Swapping on Solaris

On Jan 19, 2005, at 10:40 AM, Kevin Schroeder wrote:

> I may be asking the question the wrong way, but when I start up
> PostgreSQL swap is what gets used the most of.  I've got 1282MB free
> RAM right now and and 515MB swap in use.  Granted, swap file usage
> probably wouldn't be zero, but I would guess that it should be a lot
> lower so something must be keeping PostgreSQL from using the free RAM
> that my system is reporting.  For example, one of my postgres
> processes is 201M in size but on 72M is resident in RAM.  That extra
> 130M is available in RAM, according to top, but postgres isn't using
> it.

Can you please give us your exact shared_buffer and sort_mem settings?
This will help greatly.  As a general thing, we say don't use more than
10k shared bufs unless you have done testing and enjoy a benefit.
Managing all those buffers isn't free.

I'm also not sure how Solaris reports shared memory usage for apps... a
lot of that could be shared mem.

Can you watch say, vmstat 1 for a minute or two while PG is running and
see if you're actually swapping?

--
Jeff Trout <jeff@jefftrout.com>
http://www.jefftrout.com/
http://www.stuarthamm.net/