Message-ID: <45DF2204.7010906@archonet.com>
Date: Fri, 23 Feb 2007 17:19:00 +0000
From: Richard Huxton <dev@archonet.com>
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To: "Campbell, Lance" <lance@uiuc.edu>
Cc: pgsql-performance@postgresql.org
Subject: Re: Recommended Initial Settings
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Campbell, Lance wrote:
> Richard,
> Thanks for your reply.  
> 
> You said:
> "Your operating-system should be doing the caching for you."
> 
> My understanding is that as long as Linux has memory available it will
> cache files.  Then from your comment I get the impression that since
> Linux would be caching the data files for the postgres database it would
> be redundant to have a large shared_buffers.  Did I understand you
> correctly?

That's right - PG works with the O.S. This means it *might* not be a big 
advantage to have a large shared_buffers.

On older versions of PG, the buffer management code wasn't great with 
large shared_buffers values too.

-- 
   Richard Huxton
   Archonet Ltd