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From: David Brown <david.brown@hesbynett.no>
To: John Robinson <john.robinson@anonymous.org.uk>
Cc: NeilBrown <neilb@suse.de>,
	Oliver Martin <oliver@volatilevoid.net>,
	linux-raid@vger.kernel.org
Subject: Re: Creating a 3-disk RAID6 array
Date: Fri, 18 May 2012 09:24:23 +0200	[thread overview]
Message-ID: <4FB5F927.1030802@hesbynett.no> (raw)
In-Reply-To: <4FB50573.6020604@anonymous.org.uk>

On 17/05/2012 16:04, John Robinson wrote:
> On 17/05/2012 14:18, David Brown wrote:
> [...]
>> Theoretically, a 3-disk RAID6 is like a 2-disk RAID5 or a 1-disk RAID1 -
> [...]
>> I can't think of any good reason for it /not/ to support 3-disk
>> RAID6, as there is nothing in the algorithms to hinder it.
>
> I've a vague recollection of Peter Anvin saying the implementation is
> optimised in such a way that it won't work.
>

Okay, optimised implementation is a good reason for not supporting it! 
I only know the theory, I haven't studied the implementation well enough 
yet.  (One day, when I get time... :-)

> Cheers,
>
> John.
>

  reply	other threads:[~2012-05-18  7:24 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-17  1:24 Creating a 3-disk RAID6 array Oliver Martin
2012-05-17  1:38 ` NeilBrown
2012-05-17 13:18   ` David Brown
2012-05-17 14:04     ` John Robinson
2012-05-18  7:24       ` David Brown [this message]
2012-05-18  7:30       ` H. Peter Anvin
2012-05-18  7:57         ` NeilBrown
2012-05-19  0:04           ` H. Peter Anvin
2012-05-17 21:02   ` Dan Williams
2012-05-17 23:27     ` Oliver Martin
2012-05-17  4:22 ` Bill Davidsen
2012-05-18  2:36 ` Stan Hoeppner

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