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From: "H. Peter Anvin" <hpa@zytor.com>
To: Peter Rabbitson <rabbit+list@rabbit.us>
Cc: linux-raid@vger.kernel.org
Subject: Re: Raid6 write performance
Date: Fri, 27 Feb 2009 17:04:52 -0800	[thread overview]
Message-ID: <49A88DB4.40008@zytor.com> (raw)
In-Reply-To: <49742E74.9090502@rabbit.us>

Peter Rabbitson wrote:
> Hi,
> 
> I am experimenting with raid6 on 4 drives on 2.6.27.11. The problem I am
> having is that no matter what chunk size I use, the write benchmark
> always comes out at single drive speed, although I should be seeing
> double drive speed (read speed is at near 4x as expected).

I have no idea why you "should" be seeing double drive speed.  All
drives have to be written, so you'd logically see single drive speed.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.


  parent reply	other threads:[~2009-02-28  1:04 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-01-19  7:40 Raid6 write performance Peter Rabbitson
2009-01-19  8:10 ` thomas62186218
2009-01-19  9:07   ` NiftyFedora Mitch
2009-01-26 18:47     ` Bill Davidsen
2009-01-19 12:48   ` Keld Jørn Simonsen
2009-01-19 12:50     ` Peter Rabbitson
2009-01-19 10:37 ` Peter Rabbitson
2009-01-19 10:58   ` Bernd Schubert
2009-01-19 11:01     ` Peter Rabbitson
2009-01-19 11:08       ` Bernd Schubert
2009-02-28  1:04 ` H. Peter Anvin [this message]
2009-03-01 19:12   ` Michał Przyłuski
2009-03-01 20:35     ` H. Peter Anvin
2009-03-01 19:19   ` Peter Rabbitson
2009-03-13 17:11     ` Bill Davidsen

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