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Date: Thu, 3 Sep 2009 10:28:56 +1000
From: Emil Mikulic <emikulic@gmail.com>
To: Olivier Smedts <olivier@gid0.org>
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Cc: "Derek \(freebsd lists\)" <482254ac@razorfever.net>,
	freebsd-current@freebsd.org
Subject: Re: siis/atacam/ata/gmirror 8.0-BETA3 disk performance
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On Wed, Sep 02, 2009 at 04:36:29PM +0200, Olivier Smedts wrote:
> 2009/9/2 Emil Mikulic <emikulic@gmail.com>:
> > Stripe will give you higher throughput.
> > Mirror will give you more random seeks per second.
> 
> And higher read throughput.

If you've got two streaming reads in parallel, and get lucky with disk
scheduling, you can get higher aggregate throughput.

But for the single linear scan that Derek and I have been benchmarking,
I don't see how mirror would give a higher read throughput.  Both disks
are spinning at the same speed and their heads are in the same
positions.

--Emil