Message-ID: <50858F7B.4040802@optionshouse.com>
Date: Mon, 22 Oct 2012 13:24:59 -0500
From: Shaun Thomas <sthomas@optionshouse.com>
Reply-To: <sthomas@optionshouse.com>
Organization: Peak6
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To: "Franklin, Dan (FEN)" <Dan.Franklin@pearson.com>
CC: Claudio Freire <klaussfreire@gmail.com>,
 <pgsql-performance@postgresql.org>
Subject: Re: Tons of free RAM. Can't make it go away.
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On 10/22/2012 01:20 PM, Franklin, Dan (FEN) wrote:

> http://blog.jcole.us/2010/09/28/mysql-swap-insanity-and-the-numa-archite
> cture/

Yeah, I remember reading that a while back. While interesting, it 
doesn't really apply to PG, in that unlike MySQL, we don't allocate any 
large memory segments directly to any large block. With MySQL, it's not 
uncommon to dedicate over 50% of RAM to the MySQL process itself, but I 
don't often see PG systems with more than 8GB in shared_buffers.

All the rest should be available for random allocation in general. At 
least, in theory.

-- 
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-444-8534
sthomas@optionshouse.com

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