From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roy Sigurd Karlsbakk <roy@karlsbakk.net>
Subject: Re: SV: RAID-6 support in kernel?
Date: Tue, 4 Jun 2002 14:59:55 +0200
Sender: linux-raid-owner@vger.kernel.org
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To: Dale Stephenson <dale.stephenson@quantum.com>, 'Kasper Dupont' <kasperd@daimi.au.dk>
Cc: Christian Vik <cvik@vanadis.no>, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org
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> Of course, for a 4 drive setup there's no reason to use RAID 6 at all (RAID
> 10 will withstand any two drive failure if you only use 4 drives), but
> that's the reasoning.  I think the best way to deal with the read-modify
> write problem for RAID 6 is to use a small chunk size and deal with NxN
> chunks as a unit.  But YMMV.

RAID10 will _not_ withstand any two-drive fail in a 4-drive scenario. If D1 
and D3 fail, you're fscked

D1 D2
D3 D4

-- 
Roy Sigurd Karlsbakk, Datavaktmester

Computers are like air conditioners.
They stop working when you open Windows.