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Subject: Re: [Qemu-devel] [virtio-dev] Re: [PATCH] qemu: Introduce
 VIRTIO_NET_F_STANDBY feature bit to virtio_net
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To: Siwei Liu <loseweigh@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>, "Samudrala, Sridhar" <sridhar.samudrala@intel.com>, Alexander Duyck <alexander.h.duyck@intel.com>, virtio-dev@lists.oasis-open.org, aaron.f.brown@intel.com, Jiri Pirko <jiri@resnulli.us>, Jakub Kicinski <kubakici@wp.pl>, Netdev <netdev@vger.kernel.org>, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, konrad.wilk@oracle.com, boris.ostrovsky@oracle.com, Joao Martins <joao.m.martins@oracle.com>, Venu Busireddy <venu.busireddy@oracle.com>, vijay.balakrishna@oracle.com

On Fri, 22 Jun 2018 17:05:04 -0700
Siwei Liu <loseweigh@gmail.com> wrote:

> On Fri, Jun 22, 2018 at 3:33 PM, Michael S. Tsirkin <mst@redhat.com> wrote:
> > I suspect the diveregence will be lost on most users though
> > simply because they don't even care about vfio. They just
> > want things to go fast.  
> 
> Like Jason said, VF isn't faster than virtio-net in all cases. It
> depends on the workload and performance metrics: throughput, latency,
> or packet per second.

So, will it be guest/admin-controllable then where the traffic flows
through? Just because we do have a vf available after negotiation of
the feature bit, it does not necessarily mean we want to use it? Do we
(the guest) even want to make it visible in that case?