Public bug reported: I've noticed a significant network performance regression when using vde_switch, starting about one week ago (10/05/2012); before that date, I used to get about 1.5 Gbits host to guest, but now I can only get about 320 Mbits; I didn't find any modification in net/vde.*, just in hw/virtio*.
My command line: qemu-system-i386 -cdrom /bpd/bpd.iso -m 512 -boot d -enable-kvm \ -localtime -ctrl-grab -usbdevice tablet \ -device virtio-net-pci,mac=52:54:00:18:01:01,netdev=vde0,tx=bh,ioeventfd=on,x-txburst=32 \ -netdev vde,id=vde0 -vga std -tb-size 2M -cpu host -clock unix My host runs a kernel 3.6.1 and my guest runs a kernel 3.5.4; the same problem happens with other host and guest versions, too. I know there are better ways of running a guest, but using vde I get a cleaner environment in the host (just one tun/tap interface to manage...), which is quite good when running some accademic experiments. Interestingly, at the same time I've noticed a performance enhancement of about 25~30 % when using a tun/tap interface, bridged or not. Thank you, very much. Edivaldo de Araujo Pereira ** Affects: qemu Importance: Undecided Status: New -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1066055 Title: Network performance regression with vde_switch Status in QEMU: New Bug description: I've noticed a significant network performance regression when using vde_switch, starting about one week ago (10/05/2012); before that date, I used to get about 1.5 Gbits host to guest, but now I can only get about 320 Mbits; I didn't find any modification in net/vde.*, just in hw/virtio*. My command line: qemu-system-i386 -cdrom /bpd/bpd.iso -m 512 -boot d -enable-kvm \ -localtime -ctrl-grab -usbdevice tablet \ -device virtio-net-pci,mac=52:54:00:18:01:01,netdev=vde0,tx=bh,ioeventfd=on,x-txburst=32 \ -netdev vde,id=vde0 -vga std -tb-size 2M -cpu host -clock unix My host runs a kernel 3.6.1 and my guest runs a kernel 3.5.4; the same problem happens with other host and guest versions, too. I know there are better ways of running a guest, but using vde I get a cleaner environment in the host (just one tun/tap interface to manage...), which is quite good when running some accademic experiments. Interestingly, at the same time I've noticed a performance enhancement of about 25~30 % when using a tun/tap interface, bridged or not. Thank you, very much. Edivaldo de Araujo Pereira To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1066055/+subscriptions