Subject: Re: [RFC] kvm tools: Implement multiple VQ for virtio-net

From: Rusty Russell <[email-masked]>
Date: Mon, 21 Nov 2011 11:11:33 +1030

On Wed, 16 Nov 2011 09:23:17 +0200, "Michael S. Tsirkin" <[email-masked]> wrote:
> On Wed, Nov 16, 2011 at 10:34:42AM +1030, Rusty Russell wrote:
> > On Mon, 14 Nov 2011 15:05:07 +0200, "Michael S. Tsirkin" <[email-masked]> 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 <[email-masked]> 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.
> 
> LLTX? It's supposed to be deprecated, isn't it?

I was referring back to "Subject: virtio net lockless ring" which
Stephen sent back in June, nothing more specific.

I assumed from his query that this was still an active area of
exploration...

Stephen?

Thanks,
Rusty.