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Date: Wed, 28 May 2008 19:57:52 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Jens =?UTF-8?B?QsOkY2ttYW4=?=" <jens.backman@gmail.com>
Cc: "Justin Piszcz" <jpiszcz@lucidpixels.com>, linux-kernel@vger.kernel.org,
       linux-raid@vger.kernel.org, xfs@oss.sgi.com
Subject: Re: Performance Characteristics of All Linux RAIDs (mdadm/bonnie++)
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On Wed, 28 May 2008 18:34:00 +0200
"Jens Bäckman" <jens.backman@gmail.com> wrote:

> On Wed, May 28, 2008 at 10:53 AM, Justin Piszcz <jpiszcz@lucidpixels.com> wrote:
> > Results:
> >
> > http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.html
> > http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.txt
> 
> Either the RAID 1 read speed must be wrong, or something is odd in the
> Linux implementation. There's six drives that can be used for reading
> at the same time, as they contain the very same data. 63MB/s
> sequential looks like what you would get from a single drive.

Which is fairly typical of a cheap desktop PC where the limitation is the
memory and PCI bridge as much as the drive.

Alan