Content-Type: text/plain; charset="utf-8"
Date: Wed, 28 Nov 2012 09:51:26 -0500
From: "Kevin Grittner" <kgrittn@mail.com>
Message-ID: <20121128145126.69300@gmx.com>
MIME-Version: 1.0
Subject: Re: Optimize update query
To: =?iso-8859-1?Q?=22Niels_Kristian_Schj=F8dt=22?=
	<nielskristian@autouncle.com>,pgsql-performance@postgresql.org
Content-Transfer-Encoding: 8bit
Precedence: bulk
Sender: pgsql-performance-owner@postgresql.org

Niels Kristian Schjødt wrote:

> PS. I'm on postgres 9.2 on a server with 32gb ram, 8 cores and
> two 3T disks in a software raid 1 setup.

In addtion to the excellent advice from Shaun, I would like to
point out a few other things.

One query runs on one core. In a test of a single query, the other
seven cores aren't doing anything. Be sure to pay attention to how
a representative workload is handled.

Unless you have tuned your postgresql.conf settings, you probably
aren't taking very good advantage of that RAM.

For heavy load you need lots of spindles and a good RAID controller
with battery-backed cache configured for write-back.

You will probably benefit from reading this page:

http://wiki.postgresql.org/wiki/SlowQueryQuestions

If you don't already have it, you will probably find Greg Smith's
book on PostgreSQL performance a great investment:

http://www.postgresql.org/docs/books/

-Kevin


-- 
Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance