From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Robinson <john.robinson@anonymous.org.uk>
Subject: Re: O_DIRECT to md raid 6 is slow
Date: Wed, 15 Aug 2012 12:50:55 +0100
Message-ID: <502B8D1F.7030706@anonymous.org.uk>
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To: Andy Lutomirski <luto@amacapital.net>
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On 15/08/2012 01:49, Andy Lutomirski wrote:
> If I do:
> # dd if=/dev/zero of=/dev/md0p1 bs=8M
[...]
> It looks like md isn't recognizing that I'm writing whole stripes when
> I'm in O_DIRECT mode.

I see your md device is partitioned. Is the partition itself stripe-aligned?

Cheers,

John.