I played around with this topic on 4.2.12 and found a) no docs (it looks like there is no information on the net about using virtio-net in vbox and implications or performance tuning besides the explanation how to setup)
b) quite strange effects in combination with kernel vhost_net drivers If I load vhost_net before starting vbox, the latency of pings between linux guests using virtio-net can look like this: PING a.b.c.d 56(84) bytes of data. 64 bytes from ...: icmp_seq=1 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=2 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=3 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=4 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=5 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=6 ttl=64 time=16.0 ms 64 bytes from ...: icmp_seq=7 ttl=64 time=4.00 ms 64 bytes from ...: icmp_seq=8 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=9 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=10 ttl=64 time=24.0 ms 64 bytes from ...: icmp_seq=11 ttl=64 time=36.0 ms 64 bytes from ...: icmp_seq=12 ttl=64 time=12.0 ms 64 bytes from ...: icmp_seq=13 ttl=64 time=16.0 ms 64 bytes from ...: icmp_seq=14 ttl=64 time=192 ms 64 bytes from ...: icmp_seq=15 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=16 ttl=64 time=24.0 ms 64 bytes from ...: icmp_seq=17 ttl=64 time=36.0 ms 64 bytes from ...: icmp_seq=18 ttl=64 time=0.000 ms 64 bytes from ...: icmp_seq=19 ttl=64 time=0.000 ms ^C --- a.b.c.d ping statistics --- 19 packets transmitted, 19 received, 0% packet loss, time 18039ms rtt min/avg/max/mdev = 0.000/18.951/192.039/42.595 ms This is no worst-case scenario. I already saw times around 200-700 ms. The really odd thing about this is that the "0.000 ms" results show up _only_ if vhost_net is loaded before vbox. If it is not loaded the results start around 0.400 ms and still go up to several hundred ms. So it looks like the kernel module is used somehow. It would be very helpful if there were some doc explaining how to set up kernel on both host and guest for optimal virtio-net performance and explaining how vhost_net interferes with that setup. Is vhost_net really supported by vbox or is this working setup only a lucky coincidence? -- Regards, Stephan ------------------------------------------------------------------------------ Introducing AppDynamics Lite, a free troubleshooting tool for Java/.NET Get 100% visibility into your production application - at no cost. Code-level diagnostics for performance bottlenecks with <2% overhead Download for free and get started troubleshooting in minutes. http://p.sf.net/sfu/appdyn_d2d_ap1 _______________________________________________ VBox-users-community mailing list VBox-users-community@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/vbox-users-community _______________________________________________ Unsubscribe: mailto:vbox-users-community-requ...@lists.sourceforge.net?subject=unsubscribe
