[CoLoCo] virtualization in hardy: kvm

[Kevin Fries]

On Fri, 2008-03-14 at 18:19 -0600, Jim Hutchinson wrote:
> 
> 
> On Fri, Mar 14, 2008 at 4:45 PM, Soren Hansen <soren at ubuntu.com>
> wrote:
>         On Fri, Mar 14, 2008 at 02:57:27PM -0600, Kevin Fries wrote:
>         
> <snip>
> 
> This is an interesting discussion (no, I'm not being sarcastic) though
> it's way over my head. However, it's my understanding that "something"
> to do with VMs is now included in hardy. I am running hardy now and
> would like to play around with installing other Linux distros and
> windows (just to say I can and not 'cause it's useful) in a VM. I
> tried VMware and VirtualBox before with some success but never enough
> to be useful in any way (probably due largely to my own lack of
> knowledge). How would I go about taking advantage of this feature in
> hardy? Note, my AMD CPU is the older 939 and does not support hardware
> virtualization but I have a laptop with a core 2 that does. I'd rather
> use my AMD desktop if I can.

This is the heart of the argument.  Without hardware VT support (VT is
the flag your processor will export when you have hardware
virtualization support), KVM is pretty useless.  It will not even load
on my IBM R40 laptops.

[For anyone wondering: look in /proc/cpuinfo.  There will be a section
for each processor core you have.  Towards the bottom of the each
section will be an entry labled flags.  These are the flags that give
the capabilities of the processor.  Look for an entry in that list
called vmx.  If this is found, your processor has support for
virtualization in the processor.  This will enable KVM to work.  Xen
will also allow installation of MS Windows when vmx is present,
otherwise you are limited to OSes with Xen kernel support (i.e. Linux).
VMWare and VBox will use the hardware support when present, but will
work around it when missing]

You are better off with something else.  Xen will work Linux to Linux
without the VT support. Qemu, VMWare and VBox, will all work for any
supported client with or without VT support.

Its because of this reliance on VT that is the heart of my disagreement
with Soren.  He is more of a purist from the standpoint of use Open
Source and FOSS unless you absolutely have to.  Therefore, he is far
more willing to overlook what I see as fundamental flaws in the KVM
product.  On that dual core, KVM should work quite nicely.  Though it
has been know to have a few stability problems.  All in all tough, KVM,
given enough hardware should perform well.

-- 
Kevin Fries
Senior Linux Engineer
Computer and Communications Technology, Inc
A Division of Japan Communications Inc.