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From: Stefan Hajnoczi <stefanha@redhat.com>
To: Peter Lieven <pl@kamp.de>
Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, famz@redhat.com,
	kwolf@redhat.com, mreitz@redhat.com, pbonzini@redhat.com
Subject: Re: [Qemu-devel] [PATCH V3] block/io: optimize bdrv_co_pwritev for small requests
Date: Tue, 31 May 2016 16:39:48 -0700	[thread overview]
Message-ID: <20160531233948.GA14713@stefanha-x1.localdomain> (raw)
In-Reply-To: <1464607873-28206-1-git-send-email-pl@kamp.de>

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On Mon, May 30, 2016 at 01:31:13PM +0200, Peter Lieven wrote:
> in a read-modify-write cycle a small request might cause
> head and tail to fall into the same aligned block. Currently
> QEMU reads the same block twice in this case which is
> not necessary.
> 
> Signed-off-by: Peter Lieven <pl@kamp.de>
> ---
> v1->v2: following Paolos suggestions to simplify the if condition and
>         adjusting the comment
> v2->v3: fix iotest 077 for requests that are within the same aligned block [Fam, Kevin]
> 
>  block/io.c                 |  8 ++++++++
>  tests/qemu-iotests/077     | 12 +-----------
>  tests/qemu-iotests/077.out | 26 --------------------------
>  3 files changed, 9 insertions(+), 37 deletions(-)

Thanks, applied to my block tree:
https://github.com/stefanha/qemu/commits/block

Stefan

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      reply	other threads:[~2016-05-31 23:40 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-30 11:31 [Qemu-devel] [PATCH V3] block/io: optimize bdrv_co_pwritev for small requests Peter Lieven
2016-05-31 23:39 ` Stefan Hajnoczi [this message]

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