User Question

User Question

[Randy Broman]

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!

Re: User Question

[Cam Macdonell]

Randy Broman wrote:
> 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.

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.

> This is a home not production system, and I'd like to get the best guest
> performance possible. 

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.

> 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. 

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 :)

> Would appreciate recommendations and/or pointers to useful docs.

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

Good luck,
Cam

Re: User Question

[Randy Broman]

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



Cam Macdonell wrote:
> 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.

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.

> This is a home not production system, and I'd like to get the best guest
> performance possible. 

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.

> 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. 

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 :)

> Would appreciate recommendations and/or pointers to useful docs.

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

Good luck,
Cam