On Fri, Jul 23, 2010 at 9:37 AM, Sebastian Hetze <s.hetze@xxxxxxxxxxxx> wrote: > I did some benchmarking mainly with tbench and found virtio better > with big packages/maximum throughput and e1000 better with small > packages/latency. vhost-net improves virtio quite a lot and makes > it superior to the emulated devices. > This is what that concerns me whether i am doing anything wrong. vhost-net doesn't improve my virtio performance at all.. Thats what makes me think that i am doing someting wrong. Couls you please tell me the distribution, qemu-kvm version, guest and host kernel version, no. of cores in cpu and your cpu info? Actually my application is small packets and need low latency. I cannot use dedicated network card for pci passthrough. I want to push the virtio to work better for better latency for small packets. I dont mind sacrificing throughput. When i read that vhost-net reduces 4 to 5 times the latency of virtio, i was excited but it didn't improve my latency at all.. I am definitely missing something. Does vhost-net improves virtio latency for small packets? I tried disabling the tx timeout in the virtio-net in the qemu-kvm. It did improve the latency a lot. But still it was far less than the emulated e1000? Is there any changes that can be made to virtio-net, vhost-net to improve latency for small packets? Thanks, Bala -- 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
