Re: PostgreSQL performance problem -> tuning

On Thu, 2003-08-07 at 12:04, Yaroslav Mazurak wrote:
> scott.marlowe wrote:
>
> > On Thu, 7 Aug 2003, Yaroslav Mazurak wrote:
>
> >>Shridhar Daithankar wrote:
>
[snip]
> > My guess is that this is exactly what's happening to you, you're using so
> > much memory that the machine is running out and slowing down.
>
> > Drop shared_buffers to 1000 to 4000, sort_mem to 8192 and start over from
> > there. Then, increase them each one at a time until there's no increase
> > in speed, or stop if it starts getting slower and back off.
>
> > bigger is NOT always better.
>
> Let I want to use all available RAM with PostgreSQL.
> Without executing query (PostgreSQL is running) top say now:

You're missing the point. PostgreSQL is not designed like Oracle,
Sybase, etc.

They say, "Give me all the RAM; I will cache everything myself."

PostgreSQL says "The kernel programmers have worked very hard on
disk caching. Why should I duplicate their efforts?"

Thus, give PG only a "little" RAM, and let the OS' disk cache hold
the rest.

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