Subject: Re: Slow restoration question
From: Scott Marlowe <smarlowe@g2switchworks.com>
To: Michael Stone <mstone+postgres@mathom.us>
Cc: "Jim C. Nasby" <jnasby@pervasive.com>, pgsql-performance@postgresql.org
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Date: Wed, 03 May 2006 14:40:15 -0500

On Wed, 2006-05-03 at 14:26, Michael Stone wrote:
> On Wed, May 03, 2006 at 01:08:21PM -0500, Jim C. Nasby wrote:
> >Well, in this case the question was about random write access, which dd
> >won't show you.
> 
> That's the kind of thing you need to measure against your workload.

Of course, the final benchmarking should be your application.

But, supposed you're comparing 12 or so RAID controllers for a one week
period, and you don't even have the app fully written yet, and because
of time constraints, you'll need the server ready before the app is
done.  You don't need perfection, but you need some idea how the array
performs.  I maintain that both methodologies have their uses.  

Note that I'm referring to bonnie++ as was an earlier poster.  It
certainly seems capable of giving you a good idea of how your hardware
will behave under load.