[libvirt-users] How can a bridge be optimized?

[Henrik Ahlgren]

On 06/11/2012 06:34 PM, Whit Blauvelt wrote:
> Looking into background info on these, it looks like SR-IOV capability is
> specific to certain NICs and not documented for KVM/libvirt in any obvious
> place. Maybe I just didn't find it.

I think SR-IOV is more for high-end 10 GigE networks; with 1 GigE NICs
and fairly modern hardware you should get decent performance (almost
wire-speed) with just simple virtio + bridge setup.

Also, make sure you have the vhost_net module loaded (or kernel compiled
with CONFIG_VHOST_NET=y), recent (0.9.0 and newer I believe?) libvirt
versions should detect it and enable vhost=on with QEMU/KVM
automatically. That should give you some further performance boost.

I agree that there is some room for improvement in libvirt documentation
regarding the network configuration.