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Date: Thu, 19 Jan 2006 10:33:27 -0500 (EST)
From: Mark Hahn <hahn@physics.mcmaster.ca>
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To: Neil Brown <neilb@suse.de>
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>,
       "Lincoln Dale (ltd)" <ltd@cisco.com>, Michael Tokarev <mjt@tls.msk.ru>,
       <linux-raid@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
       "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Subject: RE: [PATCH 000 of 5] md: Introduction
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>  Use either for raid0 (I don't think dm has particular advantages
>      for md or md over dm).

I measured this a few months ago, and was surprised to find that 
DM raid0 was very noticably slower than MD raid0.  same machine,
same disks/controller/kernel/settings/stripe-size.  I didn't try
to find out why, since I usually need redundancy...

regards, mark hahn.