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Date: Mon, 12 May 2003 12:32:16 -0400
From: Chuck Ebbert <76306.1226@compuserve.com>
Subject: Re: Two RAID1 mirrors are faster than three
To: Clemens Schwaighofer <cs@tequila.co.jp>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Clemens Schwaighofer wrote:

> Why three drives in a Raid1? Raid one is just mirror, or is the third
> drive like a "hot" replace drive if one of the others fail?

  The goal is to get better (read) performance, as well as extra
redundancy.  The system is supposed to balance reads among the
available drives but in this case it breaks when there are more
than two disks.

  I have a "changes way too much code" patch that fixes this; guess
I should at least post it and see what happens...