User Question

I'm running Kubuntu Jaunty 9.04 on an AMD Phenom II 910, with a custom 2.6.28 kernel. I want to install KVM with a Windows XP guest. Apologies I'm confused as to exactly what to install ....

-I can (should?) apt-get install KVM and/or QEMU from the Jaunty archives. -I can configure KVM into my custom kernel using CONFIG_KVM=m, CONFIG_KVM_AMD=m and a couple other .config options.
-I can download, compile and install kvm-84 from source for my kernel On this basis I would presumably invoke qemu-system-x86_64 from the install directory.

This is a home not production system, and I'd like to get the best guest performance possible. I'm a little confused between KVM and QEMU ... I know there's a KVM kernel module(s) plus the facility to run the virtual guest, but I'm unsure which of the above choices to use. Would appreciate recommendations and/or pointers to useful docs.

Thanks!

Hi Randy,

I follow the third method. Compiling the kvm-84 tarball will build both the kernel modules and the userspace qemu-system-x64_84 for you and install them for you.

Getting the best performance possible will depend on your use of devices. For network performance do not use the "user" network stack it's really slow; use vde or bridged networking. Docs for this are here (http://www.linux-kvm.org/page/Networking). VDE has no description (yet), but google will help.

Qemu is an system emulator that emulate numerous architectures. With KVM, Qemu is used in the userspace to manage virtual devices and allocate memory for the VMs (no processor emulation is done; Qemu is only used for x86 on x86 within KVM), but kernel modules are added to take advantage of hardware virtualization support. It's well known that the names of executables can be confusing :)

linux-kvm.org is the place to start. Specifically the how-to section.

Good luck,
Cam

Thanks Cam for the information, I've compiled and installed the kvm-84 tarball, I'm running modules KVM and KVM_AMD, and I can start my WinXP guest successfully with qemu-system-x86_64. I've compiled and installed vde, but I can't get vde networking working in the guest. My Kubuntu host is on 192.168.0 network, and I did:

% sudo vde_switch -t tap0 -daemon
%sudo ifconfig tap0 192.168.1.1 netmask 255.255.255.0

When I do an ifconfig -a, both my host eth0 and tap0 appear to show up correctly on the host (?). When I start qemu-system-x86_64 with it's several options, I'm confused as to how to specify the

-net vde[,vlan=n][,name=str][,sock-socketpath][,port=n][,group=groupname][,mode=octalmode]

options. I have only one guest on the system/network. The guest starts, and I've set it's IP at 192.168.1.2 and gateway 192.168.1.1, but no connectivity.

Another question, should I use -net model=virtio, and if so where do I get the WinXP driver for that?

Thanks, Randy

Hi Randy,

I follow the third method. Compiling the kvm-84 tarball will build both the kernel modules and the userspace qemu-system-x64_84 for you and install them for you.

Getting the best performance possible will depend on your use of devices. For network performance do not use the "user" network stack it's really slow; use vde or bridged networking. Docs for this are here (http://www.linux-kvm.org/page/Networking). VDE has no description (yet), but google will help.

Qemu is an system emulator that emulate numerous architectures. With KVM, Qemu is used in the userspace to manage virtual devices and allocate memory for the VMs (no processor emulation is done; Qemu is only used for x86 on x86 within KVM), but kernel modules are added to take advantage of hardware virtualization support. It's well known that the names of executables can be confusing :)

linux-kvm.org is the place to start. Specifically the how-to section.

Good luck,
Cam