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From: Christoph Dittmann <linux-raid@christoph-d.de>
To: linux-raid@vger.kernel.org
Subject: Re: Triple-parity raid6
Date: Fri, 10 Jun 2011 14:20:40 +0200	[thread overview]
Message-ID: <4DF20C18.3030604@christoph-d.de> (raw)
In-Reply-To: <isslla$o2i$1@dough.gmane.org>

On 06/10/2011 10:45 AM, David Brown wrote:
> Making multiple parity syndromes is easy enough mathematically:

Adam Leventhal, who wrote the double parity and triple parity code for 
ZFS, mentioned on his blog [1] that going beyond triple parity poses 
significant challenges if write performance should not suffer.

In particular, it looks like a relevant math paper (originally) had a 
flaw in the claim that quad parity and above can be implemented just 
like triple parity.

I don't know the implementation you were going to use, neither am I 
knowledgeable about multi-parity in general. I only thought it might be 
relevant to add to the current discussion that other people had issues 
with implementing N-parity for N > 3.


Christoph

[1] http://blogs.oracle.com/ahl/entry/triple_parity_raid_z

  reply	other threads:[~2011-06-10 12:20 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-09  0:01 Triple-parity raid6 David Brown
2011-06-09  1:49 ` NeilBrown
2011-06-09 11:32   ` David Brown
2011-06-09 12:04     ` NeilBrown
2011-06-09 19:19       ` David Brown
2011-06-10  3:22       ` Namhyung Kim
2011-06-10  8:45         ` David Brown
2011-06-10 12:20           ` Christoph Dittmann [this message]
2011-06-10 14:28             ` David Brown
2011-06-11 10:13               ` Piergiorgio Sartor
2011-06-11 11:51                 ` David Brown
2011-06-11 13:18                   ` Piergiorgio Sartor
2011-06-11 14:53                     ` David Brown
2011-06-11 15:05                       ` Joe Landman
2011-06-11 16:31                         ` David Brown
2011-06-11 16:57                           ` Joe Landman
2011-06-12  9:05                             ` David Brown
2011-06-11 17:14                           ` Joe Landman
2011-06-11 18:05                             ` David Brown
2011-06-10  9:03       ` David Brown
2011-06-10 13:56       ` Bill Davidsen
2011-06-09 22:42 ` David Brown

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