Bruce Momjian says it much better than I could:
http://www.ca.postgresql.org/docs/momjian/hw_performance/
You also might take a look at some of your most resource draining
queries with 'explain' in psql.
Jason Earl
Francisco Reyes <lists@natserv.com> writes:
> On Sat, 27 Oct 2001, Keary Suska wrote:
>
> > If I had a guess I would say the problem isn't with postgres, if your system
> > CPU usage is 50%. I haven't had a system go over 20%, even under extreme
> > duress. Are you by chance using Linux with a 2.4 kernel? The swap mechanism
> > in 2.4 was terrible (it may have been fixed by now). What is you memory and
> > virtual memory performance like? Extensive swapping could be at least
> > partially responsible.
> >
> > Keary Suska
> > Esoteritech, Inc.
> > "Leveraging Open Source for a better Internet"
>
> coming very late to this thread..
> In general what settings can one change to enhance performance. I too have
> a machine with high CPU utilization when doing a query. Said query does a
> sequential scan.
>
> When I use 'top' to see how much memory is been used by postgresql it is
> only using 8MB. This machine is very lightly used so I would like to give
> PostgreSQL more memory.
>
>
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