From: Greg Stark <gsstark@mit.edu>
To: Pierre C <lists@peufeu.com>
Cc: Nikolas Everett <nik9000@gmail.com>
Cc: Greg Smith <greg@2ndquadrant.com>
Cc: Dave Crooke <dcrooke@gmail.com>
Cc: Paul McGarry <paul@paulmcgarry.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: shared_buffers advice
Date: Tue, 16 Mar 2010 14:51:11 +0000
Message-ID: <407d949e1003160751i43aaa472j4f90c4cf92a1e011@mail.gmail.com> (raw)
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On Tue, Mar 16, 2010 at 1:48 PM, Pierre C <lists@peufeu.com> wrote:
> Actually, I meant that in the case of a seq scan, PG will try to use just a
> few buffers (a ring) in shared_buffers instead of thrashing the whole
> buffers. But if there was actually a lot of free space in shared_buffers, do
> the pages stay, or do they not ?
They don't. The logic only kicks in if the table is expected to be >
1/4 of shared buffers though.
--
greg
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Cc: gsstark@mit.edu, lists@peufeu.com, nik9000@gmail.com, greg@2ndquadrant.com, dcrooke@gmail.com, paul@paulmcgarry.com
Subject: Re: shared_buffers advice
In-Reply-To: <407d949e1003160751i43aaa472j4f90c4cf92a1e011@mail.gmail.com>
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