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Date: Fri, 18 Feb 2011 13:23:51 +0100
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 3/3 v2] block/nbd: Make the NBD block device
	use the AIO interface
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To: Nicholas Thomas <nick@bytemark.co.uk>
Cc: stefanha@gmail.com, qemu-devel@nongnu.org

Am 18.02.2011 13:16, schrieb Nicholas Thomas:
> On Thu, 2011-02-17 at 19:28 +0000, Nicholas Thomas wrote:
> 
>> Additional testing has revealed that this code breaks the stock
>> nbd-server (the one on sourceforge) when large (well, 1.3MiB) write
>> requests are sent to it.
> 
> ....NBD has a limit of 1MB on the size of write requests.
> NBD_BUFFER_SIZE in qemu-nbd.c - and I'm sure that's what's knocking out
> the standard NBD server too.
> 
> I didn't see any option to tell QEMU to split up writes to a certain
> size before handing them off to the block driver, so I split the writes
> up into multiple acbs. Reworked patch:

Splitting it up manually sounds right.

I haven't had a close look at your patches yet, but one thing that I
noticed is that your patches are corrupted by line wraps. Please
consider using git-send-email to avoid this kind of trouble or configure
your mailer so that it stops doing this.

Kevin