Re: Effective Cache Size

On Tue, 1 Jul 2003 15:50:14 +0200 , Howard Oblowitz
<HowardO(at)LEWIS-STORES(dot)com> wrote:
>What then will be the effect of setting this too high?

The planner might choose an index scan where a sequential scan would
be faster.

>And too low?

The planner might choose a sequential scan where an index scan would
be faster.

>How does it impact on other applications eg Java ?

It doesn't -- at least not directly. (There could be very subtle
effects when Postgres does a sequential scan over a large relation
thus pushing everything else out of the cache, where an index scan
would have read only a small number of pages. Or when a large index
scan turns your machine from CPU bound to I/O bound.)

Servus
Manfred