Date: Tue, 17 Jan 2006 20:01:29 -0700
From: Michael Loftis <mloftis@wgops.com>
To: Phillip Susi <psusi@cfl.rr.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: FYI: RAID5 unusably unstable through 2.6.14
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--On January 17, 2006 9:10:56 PM -0500 Phillip Susi <psusi@cfl.rr.com> 
wrote:

> I understood you to be saying that a raid-5 was less reliable than a
> single disk, which it is not.  Maybe I did not read correctly.  Yes, a 3
> + n disk raid-5 has a higher chance of failure than a 3 disk raid-5, but
> only slightly so, and in any case, a 3 disk raid-5 is FAR more reliable
> than a single drive, and only slightly less reliable than a two disk
> raid-1 ( though you get 3x the space for only 50% higher cost, so 6x
> cheaper cost per byte of storage ).


Yup we're on the same page, we just didn't think we were.  It happens :) 
R-5 (in theory) could be less reliable than a mirror or possibly a single 
drive, but it'd take a pretty obscene number of drives with excessively 
large strip size.
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