On Mon, Aug 10, 2009 at 03:51:12PM -0500, Anthony Liguori wrote: > Michael S. Tsirkin wrote: >> This adds support for vhost-net virtio kernel backend. >> >> This is RFC, but works without issues for me. >> >> Still needs to be split up, tested and benchmarked properly, >> but posting it here in case people want to test drive >> the kernel bits I posted. >> > > Any rough idea on performance? Better or worse than userspace? > > Regards, > > Anthony Liguori Well, I definitely see some gain in latency. Here's a simple test over a 1G ethernet link (host to guest): Native: [root@qus18 ~]# netperf -H 11.0.0.1 -t udp_rr UDP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 11.0.0.1 (11.0.0.1) port 0 AF_INET Local /Remote Socket Size Request Resp. Elapsed Trans. Send Recv Size Size Time Rate bytes Bytes bytes bytes secs. per sec 126976 126976 1 1 10.00 10393.23 124928 124928 vhost virtio: [root@qus18 ~]# netperf -H 11.0.0.3 -t udp_rr UDP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 11.0.0.3 (11.0.0.3) port 0 AF_INET Local /Remote Socket Size Request Resp. Elapsed Trans. Send Recv Size Size Time Rate bytes Bytes bytes bytes secs. per sec 126976 126976 1 1 10.00 8169.58 124928 124928 Userspace virtio: [root@qus18 ~]# netperf -H 11.0.0.3 -t udp_rr UDP REQUEST/RESPONSE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 11.0.0.3 (11.0.0.3) port 0 AF_INET Local /Remote Socket Size Request Resp. Elapsed Trans. Send Recv Size Size Time Rate bytes Bytes bytes bytes secs. per sec 126976 126976 1 1 10.00 2029.49 124928 124928 Part of it might be that tx mitigation does not come into play with vhost. I need to disable it in qemu and see. -- MST -- 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
