Re: [PERFORM] Quad processor options

On Tue, 11 May 2004 15:46:25 -0700, Paul Tuckfield <paul(at)tuckfield(dot)com>
wrote:
>- the "cache" column shows that linux is using 2.3G for cache. (way too
>much)

There is no such thing as "way too much cache".

> you generally want to give memory to postgres to keep it "close" to
>the user,

Yes, but only a moderate amount of memory.

> not leave it unused to be claimed by linux cache

Cache is not unused memory.

>- I'll bet you have a low value for shared buffers, like 10000. On
>your 3G system
> you should ramp up the value to at least 1G (125000 8k buffers)

In most cases this is almost the worst thing you can do. The only thing
even worse would be setting it to 1.5 G.

Postgres is just happy with a moderate shared_buffers setting. We
usually recommend something like 10000. You could try 20000, but don't
increase it beyond that without strong evidence that it helps in your
particular case.

This has been discussed several times here, on -hackers and on -general.
Search the archives for more information.

Servus
Manfred