Re: preloading indexes

The caching appears to disappear overnight. The environment is not in
production yet so I'm the only one on it. 

Is there a time limit on the length of time in cache? I believe there is
sufficient RAM, but maybe I need to look again.

s 

-----Original Message-----
From: pgsql-performance-owner@postgresql.org
[mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Andrew Sullivan
Sent: Wednesday, November 03, 2004 12:35 PM
To: pgsql-performance@postgresql.org
Subject: Re: [PERFORM] preloading indexes

On Wed, Nov 03, 2004 at 12:12:43PM -0700, stuff@opensourceonline.com wrote:
> That's correct - I'd like to be able to keep particular indexes in RAM
> available all the time

If these are queries that run frequently, then the relevant cache
will probably remain populated[1].  If they _don't_ run frequently, why
do you want to force the memory to be used to optimise something that
is uncommon?  But in any case, there's no mechanism to do this.

A

[1] there are in fact limits on the caching: if your data set is
larger than memory, for instance, there's no way it will all stay
cached.  Also, VACUUM does nasty things to the cache.  It is hoped
that nastiness is fixed in 8.0.

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
The plural of anecdote is not data.
		--Roger Brinner

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