Re: performance tuning: shared_buffers, sort_mem; swap - Mailing list pgsql-admin

From Bruce Momjian
Subject Re: performance tuning: shared_buffers, sort_mem; swap
Date
Msg-id 200208131556.g7DFuH008873@candle.pha.pa.us
Whole thread Raw
In response to performance tuning: shared_buffers, sort_mem; swap  (Thomas O'Connell <tfo@monsterlabs.com>)
Responses Re: performance tuning: shared_buffers, sort_mem; swap  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-admin
Thomas O'Connell wrote:
> so a while back, i think i recall a post from Bruce Momjian describing
> an optimum setup for shared_buffers at 25% of available physical memory
> and sort_mem at 4% of available physical memory.

Yes, that was the numebers to start with.

> the caveat was to watch for swap activity when these values were being
> set. so my question is, how much swapping is too much, and is there a
> way to determine whether postgres is the process causing the swapping?

Well, it doesn't really matter who is causing the swapping.  If you have
more of a load on your machine that RAM can hold, you are better off
reducing your PostgreSQL shared buffers.

--
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