Hi, Barak, We've tried vhost-net in kvm-arm on arndale Exynos-5250 board (it requires some patches in qemu and kvm, of course). It works (without irqfd support), however, the performance does not increase much. The throughput (iperf) of virtio-net and vhost-net are 93.5Mbps and 93.6Mbps respectively. I thought the result are because both virtio-net and vhost-net almost reached the limitation of 100Mbps Ethernet.
The good news is that we even ported vhost-net in our kvm-a9 hypervisor (refer: http://academic.odysci.com/article/1010113020064758/evaluation-of-a-server-grade-software-only-arm-hypervisor), and the throughput of vhost-net on that platform (with 1Gbps Ethernet) increased from 323Mbps to 435Mbps. -- Ying-Shiuan Pan, H Div., CCMA, ITRI, TW ---- Best Regards, 潘穎軒Ying-Shiuan Pan 2014/1/13 Peter Maydell <peter.mayd...@linaro.org> > On 12 January 2014 21:49, Barak Wasserstrom <wba...@gmail.com> wrote: > > Thanks - I got virtio-net-device running now, but performance is > terrible. > > When i look at the guest's ethernet interface features (ethtool -k eth0) > i > > see all offload features are disabled. > > I'm using a virtual tap on the host (tap0 bridged to eth3). > > On the tap i also see all offload features are disabled, while on br0 and > > eth3 i see the expected offload features. > > Can this explain the terrible performance i'm facing? > > If so, how can this be changed? > > If not, what else can cause such bad performance? > > Do you know if vhost_net can be used on ARM Cortex A15 host/guest, even > > though the guest doesn't support PCI & MSIX? > > I have no idea, I'm afraid. I don't have enough time available to > investigate performance issues at the moment; if you find anything > specific you can submit patches... > > thanks > -- PMM > >
