Message-ID: <500F1239.80104@kickstone.com>
Date: Tue, 24 Jul 2012 22:23:05 +0100
From: John Lister <john.lister@kickstone.com>
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To: Claudio Freire <klaussfreire@gmail.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Linux memory zone reclaim
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On 24/07/2012 21:12, Claudio Freire wrote:
> On Tue, Jul 24, 2012 at 3:41 PM, Claudio Freire <klaussfreire@gmail.com> wrote:
>> On Tue, Jul 24, 2012 at 3:36 PM, John Lister <john.lister@kickstone.com> wrote:
>>> Do you have a suggestion about how to do that? I'm running Ubuntu 12.04 and
>>> PG 9.1, I've modified pg_ctlcluster to cause pg_ctl to use a wrapper script
>>> which starts the postmaster using a numactl wrapper, but all subsequent
>>> client processes are started with interleaving enabled as well. Any ideas
>>> how to make just the postmaster process start with interleaving?
>> postmaster should call numactl right after forking:
>> http://linux.die.net/man/2/set_mempolicy
> Something like the attached patch (untested)
Cheers, I'll give it a go, I wonder if this is likely to be integrated 
into the main code? As has been mentioned here before, postgresql isn't 
as badly affected as mysql for example, but I'm wondering if the trend 
to larger memory and more cores/nodes means it should be offered as an 
option? Although saying that I've read that 10Gb of shared buffers may 
be enough even in big machines 128+Gb ram..

Thoughts?

John