On Fri, 06 Jul 2012 11:20:06 +0800 Jason Wang <jasowang@xxxxxxxxxx> wrote: > On 07/05/2012 08:51 PM, Sasha Levin wrote: > > On Thu, 2012-07-05 at 18:29 +0800, Jason Wang wrote: > >> @@ -1387,6 +1404,10 @@ static int virtnet_probe(struct virtio_device *vdev) > >> if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) > >> vi->has_cvq = true; > >> > >> + /* Use single tx/rx queue pair as default */ > >> + vi->num_queue_pairs = 1; > >> + vi->total_queue_pairs = num_queue_pairs; > > The code is using this "default" even if the amount of queue pairs it > > wants was specified during initialization. This basically limits any > > device to use 1 pair when starting up. > > > > Yes, currently the virtio-net driver would use 1 txq/txq by default > since multiqueue may not outperform in all kinds of workload. So it's > better to keep it as default and let user enable multiqueue by ethtool -L. > I would prefer that the driver sized number of queues based on number of online CPU's. That is what real hardware does. What kind of workload are you doing? If it is some DBMS benchmark then maybe the issue is that some CPU's need to be reserved. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
