[Discuss] choice of hypervisor (was gracefully shutdown guests)

[me at mattgillen.net (Matthew Gillen)]

On 06/03/2013 12:52 PM, Edward Ned Harvey (blu) wrote:
> Before there was kvm, there was xen.  And to this day, they both
> still exist and going strong.  But I think redhat and debian (Or
> Linus?  Somebody) didn't like the direction xen was going (or
> something like that) so a couple years ago, they switched over to kvm
> by default instead of xen.

The history is a little more convoluted.  Redhat got on board with Xen 
because at the time it was the more advanced solution.  With RH's 
backing (it was the default virtualization solution in RHEL for some 
time) Xen got a lot of early traction.  The problem was the patchset to 
enable Xen was pretty invasive, and Linus hated it.

Linus much preferred the QEMU/KVM approach, and basically said he'd 
never bring Xen into the mainline.  Since RH has a policy (a wise one 
IMHO) to push their own improvements to the upstream projects, they were 
left in a bind: if they continued with Xen, the maintenance of Xen would 
be entirely up to them.  That was a losing proposition.

So basically at this point everyone has thrown their lot in with 
QEMU/KVM and Xen is pretty much abandoned except for some researchers.

> I have never been very impressed with either xen or kvm,

I've been pretty happy lately with Win7 as a kvm guest on my laptop, but 
it was only usable once I had a laptop with a boatload of memory.  YMMV, 
obviously; I'm not using win7 for any media playback, it's pretty much 
strictly to run M$ Office.

Matt