Message-ID: <3DA2DE82.1AC84934@Yahoo.com>
Date: Tue, 08 Oct 2002 09:32:50 -0400
From: Jan Wieck <JanWieck@Yahoo.com>
Organization: Home
MIME-Version: 1.0
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: David Blood <david@matraex.com>, pgsql-general@postgresql.org
Subject: Re: Pinning a table into memory
References: <03a301c26bc5$a799a970$1f00a8c0@redwood>
	<25545.1033757267@sss.pgh.pa.us>
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Tom Lane wrote:
> 
> "David Blood" <david@matraex.com> writes:
> > In Oracle you can Pin large objects into memory to prevent frequent
> > reloads. Is there anyway to do this with Postgres?
> 
> I can never understand why people think this would be a good idea.
> If you're hitting a table frequently, it will stay in memory anyway
> (either in Postgres shared buffers or kernel disk cache).  If you're
> not hitting it frequently enough to keep it swapped in, then whatever
> is getting swapped in instead is probably a better candidate to be
> occupying the space. 

As I understand it, he's looking for a mechanism to prevent a single
sequential scan on a table, larger than the buffer cache, to kick out
everything else at once. But I agree with you that pinning other objects
is just mucking with the symptoms instead of curing the desease.


Jan

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