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Date: Wed, 17 Aug 2011 17:08:31 +0200
Subject: Re: Tuning Tips for a new Server
From: "Tomas Vondra" <tv@fuzzy.cz>
To: "Ogden" <lists@darkstatic.com>
Cc: "Andy Colson" <andy@squeakycode.net>,
 pgsql-performance@postgresql.org
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On 17 Srpen 2011, 16:28, Ogden wrote:
>  I was wondering what the best parameters would be with my new setup. The
> work_mem obviously will increase as will everything else as it's a 64Gb
> machine as opposed to a 16Gb machine. The configuration I posted was for
> a 16Gb machine but this new one is 64Gb. I needed help in how to jump
> these numbers up.

Well, that really depends on how you come to the current work_mem settings.

If you've decided that with this amount of work_mem the queries run fine
and higher values don't give you better performance (because the amount of
data that needs to be sorted / hashed) fits into the work_mem, then don't
increase it.

But if you've just set it so that the memory is not exhausted, increasing
it may actually help you.

What I think you should review is the amount of shared buffers,
checkpoints and page cache settings (see this for example
http://notemagnet.blogspot.com/2008/08/linux-write-cache-mystery.html).

Tomas