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Date: Thu, 23 May 2013 15:41:41 +0200
From: Bob Marley <bobmarley@shiftmail.org>
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To: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
CC: Chris Mason <chris.mason@fusionio.com>,
        "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: Re: raid6: rmw writes all the time?
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On 23/05/2013 15:22, Bernd Schubert wrote:
>
> Yeah, I know and I'm using iostat already. md raid6 does not do rmw, 
> but does not fill the device queue, afaik it flushes the underlying 
> devices quickly as it does not have barrier support - that is another 
> topic, but was the reason why I started to test btrfs.

MD raid6 DOES have barrier support!