I'm running two separate KVM hosts that are showing the same network performance issue - KVM-guest is 35% slower than non-KVM (or ESXi for that matter). I'm wondering if the "Broadcom NetXtreme II BCM5708" interface is at fault. I've tried all sorts of tweaks and configurations and I've only succeeded in making the network slower. The first box is running ProxMox 1.6. The second is Ubuntu 10.04. The guests on both boxes are 64-bit Ubuntu 10.04 server installs with virtio. ProxMox guest: /usr/bin/kvm -monitor unix:/var/run/qemu-server/104.mon,server,nowait -vnc unix:/var/run/qemu-server/104.vnc,password -pidfile /var/run/qemu-server/104.pid -daemonize -usbdevice tablet -name UbuntuServer -smp sockets=2,cores=2 -nodefaults -boot menu=on -vga cirrus -tdf -k en-us -drive file=/var/lib/vz/images/104/vm-104-disk-2.raw,if=ide,index=3 -drive file=/var/lib/vz/images/104/vm-104-disk-1.raw,if=virtio,index=0,boot=on -m 1024 -net tap,vlan=0,ifname=vmtab104i0,script=/var/lib/qemu-server/bridge-vlan -net nic,vlan=0,model=virtio,macaddr=76:3F:1A:03:6D:6F Ubuntu guest: /usr/bin/kvm -S -M pc-0.12 -enable-kvm -m 1024 -smp 1 -name ubutest -uuid c0537369-fffa-9680-2f29-2e0cc0406561 -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/ubutest.monitor,server,nowait -monitor chardev:monitor -boot c -drive file=/dev/vg/ubutest,if=virtio,index=0,boot=on -net nic,macaddr=52:54:00:35:11:f1,vlan=0,model=virtio,name=virtio.0 -net tap,fd=51,vlan=0,name=tap.0 -chardev pty,id=serial0 -serial chardev:serial0 -parallel none -usb -vnc 0.0.0.0 Netperf looks like this on the Ubuntu host: Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 1048576 16384 16384 10.01 941.62 This is what I get on the Ubuntu guest for either setup: Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 1048576 16384 16384 10.00 615.65 Thank you for any guidance you can lend. -- 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
