From: Josh Berkus <josh@agliodbs.com>
Reply-To: josh@agliodbs.com
Organization: Aglio Database Solutions
To: John A Meinel <john@arbash-meinel.com>
Subject: Re: seqential vs random io
Date: Mon, 23 May 2005 15:32:35 -0700
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Cc: David Parker <dparker@tazznetworks.com>, pgsql-performance@postgresql.org
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	<429257ED.6020004@arbash-meinel.com>
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David,

> > I just got a question from one our QA guys who is configuring a RAID 10
> > disk that is destined to hold a postgresql database. The disk
> > configuration procedure is asking him if he wants to optimize for
> > sequential or random access. My first thought is that random is what we
> > would want, but then I started wondering if it's not that simple, and my
> > knowledge of stuff at the hardware level is, well, limited.....
> >
> > If it were your QA guy, what would you tell him?

Depends on the type of database.  OLTP or Web == random access.  Data 
Warehouse == sequential access.

-- 
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco