From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [RFC] kvm tools: Implement multiple VQ for virtio-net
Date: Wed, 16 Nov 2011 10:34:42 +1030
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To: "Michael S. Tsirkin" <mst@redhat.com>, Pekka Enberg <penberg@kernel.org>
Cc: Krishna Kumar <krkumar2@in.ibm.com>, kvm@vger.kernel.org, Asias He <asias.hejun@gmail.com>, virtualization@lists.linux-foundation.org, gorcunov@gmail.com, Sasha Levin <levinsasha928@gmail.com>, netdev@vger.kernel.org, mingo@elte.hu, Stephen Hemminger <shemminger@vyatta.com>
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On Mon, 14 Nov 2011 15:05:07 +0200, "Michael S. Tsirkin" <mst@redhat.com> wrote:
> On Mon, Nov 14, 2011 at 02:25:17PM +0200, Pekka Enberg wrote:
> > On Mon, Nov 14, 2011 at 4:04 AM, Asias He <asias.hejun@gmail.com> wrote:
> > > Why both the bandwidth and latency performance are dropping so dramatically
> > > with multiple VQ?
> > 
> > What's the expected benefit from multiple VQs
> 
> Heh, the original patchset didn't mention this :) It really should.
> They are supposed to speed up networking for high smp guests.

If we have one queue per guest CPU, does this allow us to run lockless?

Thanks,
Rusty.