I have installed (painfully - almost 6 hrs, though I have done the acpi tricks at cd boot) Windows XP SP2 as a kvm guest.

However, the network performance is terrible (~200 kbps with small bursts up to 2 Mbps). No matter what NIC type I use, either virtio or hypervisor default rtl8139, and from time to time I get a win32host error and ics (Windows firewall and internet connection sharing) service crashes, with no explanation in the logs (except access is denied) --> system is not stable.

This problem happened to an SP2 and a different SP3 installation, so I would assume it is a virtualization issue.

The host is Debian Squeeze (kernel upgraded to 2.6.38 from squeeze-backports - this helped a bit for the guest performance) and both kvm and libvirt are upgraded to the latest version from sid repositories. The physical machine is an HP G120 server.

I have read in several places that Windows XP can be run under kvm, but I would like to hear a "Windows XP under kvm" success story with performances near those of a VMWare 2/ESXi guest or any hints that could guide me in the right direction.

 lsmod | grep kvm
kvm_intel              49947  3
kvm                   263288  1 kvm_intel

dpkg -l | grep kvm
ii  kvm                                 1:0.14.1+dfsg-2              dummy transitional package from kvm to qemu-kvm
ii  qemu-kvm                            0.14.1+dfsg-2                Full virtualization on x86 hardware

dpkg -l | grep libvirt
ii  libvirt-bin                         0.9.2-6                      the programs for the libvirt library
ii  libvirt0                            0.9.2-6                      library for interfacing with different virtualization systems
ii  python-libvirt                      0.9.2-6                      libvirt Python bindings

/usr/bin/kvm -S -M pc-0.12 -cpu qemu32 -enable-kvm -m 1512 -smp 1,sockets=1,cores=1,threads=1 -name ss -uuid d3589b2f-a4f6-1753-7a7
f-5b27073fd97f -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/ss.monitor,server,nowait -mon chardev=charmonitor,id=monitor
,mode=readline -rtc base=localtime -boot c -drive file=/var/lib/libvirt/images/ss.img,if=none,id=drive-ide0-0-0,format=raw -device ide-drive,bus=ide.0,unit=0,
drive=drive-ide0-0-0,id=ide0-0-0 -drive file=/var/lib/libvirt/images/winxp_sata.iso,if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw -device ide-d
rive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -drive file=/var/lib/libvirt/images/ss-1.img,if=none,id=drive-virtio-disk0,format=raw -device virtio-bl
k-pci,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0 -netdev tap,fd=19,id=hostnet0 -device rtl8139,netdev=hostnet0,id=net0,mac=52:54:00:79:cc:38,
bus=pci.0,addr=0x3 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -usb -device usb-tablet,id=input0 -vnc -vga cirru
s -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4
  • Is your host processor actually VT capable? This kind of performance-suckiness is often connected with not having a CPU that is capable of hardware virtualisation – Tom O'Connor Jul 5 '11 at 23:50
  • /proc/cpuinfo has vmx flag and VT is enabled in bios ... – quaie Jul 6 '11 at 6:24
up vote 1 down vote accepted

first of all, make sure kvm modules are actually loaded using lsmod. The fact that it took you 6 hours to install, is already a serious indication of a flaw in your setup. It should take up to 20 minutes, depending on the storage speeds, on any modern host. second, if kvm is actually loaded, please post the qemu and kvm versions you're running as well as the VM command line you're using. With those, recommendations can be provided

As for real life success stories - I've been running and supporting hundreds (if not thousands) of windows deployments on kvm in various setups since 2008, and if performance issues were encountered, they always were due to hardware or misconfigurations.

the problem was caused by slow hard disks; I have a new kvm setup with xp and it works flawlessly

I haven't figured it out yet, but the hdd's were wd ears 2TB and they have this problem and this could be one reason

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