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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Tue, 27 Oct 2015 10:30:27 +0100
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Subject: Re: [Qemu-devel] 4k seq read splitting for virtio-blk - possible
	workarounds?
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To: Fam Zheng <famz@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>, Andrey Korolyov <andrey@xdel.ru>, Peter Lieven <pl@kamp.de>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Jeff Moyer <jmoyer@redhat.com>, Sergey Fionov <fionov@gmail.com>



On 27/10/2015 03:04, Fam Zheng wrote:
> > My plan is for
> > 2.6 to have fine-grained critical sections (patches written, will repost
> > during 2.5 hard freeze), 2.7 (unlikely 2.6) to have fine-grained locks,
> > and 2.8 or 2.9 to have multiqueue.
> 
> You're talking about virtio-scsi, right? What about virtio-blk? Do you think we
> should resume the "fake" virtio-blk multiqueue work on QEMU side?

Even both.  If you resume the "fake" virtio-blk multiqueue, converting
to real multiqueue at the same time as virtio-scsi should be trivial.
The difficult part of course is not the device models, it's the block
layer...

Paolo