Message-ID: <4BB9F9CE.1020106@2ndquadrant.com>
Date: Mon, 05 Apr 2010 10:55:10 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Christiaan Willemsen <cwillemsen@technocon.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Using high speed swap to improve performance?
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Christiaan Willemsen wrote:
>
> So I was thinking: Why not make a big fat array using 14 disks (raid 
> 1, 10 or 5), and make this a big and fast swap disk. Latency will be 
> lower than the SAN can provide, and throughput will also be better, 
> and it will relief the SAN from a lot of read iops.
>

Presuming that swap will give predictable performance as things go into 
and out of there doesn't sound like a great idea to me.  Have you 
considered adding that space as a tablespace and setting 
temp_tablespaces to point to it?  That's the best thing I can think of 
to use a faster local disk with lower integrity guarantees for.

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us