[CentOS] XEN or KVM - performance/stability/security?

Tue Jun 5 06:32:48 UTC 2012
Pasi Kärkkäinen <pasik at iki.fi>

On Sat, May 12, 2012 at 02:38:34PM -0400, Steve Thompson wrote:
> On Sun, 6 May 2012, Pasi Kärkkäinen wrote:
> >with "fork performance" I assume you're comparing Xen PV to KVM ?
> >Yes, PV has disadvantage (per design) for that workload, since the hypervisor
> >needs to check and verify each new process page table, and that has some performance hit.
> >For good "fork performance" you can use Xen HVM VMs, which will perform well for that workload,
> >and won't have the mentioned performance hit.
> I used both PV and HVM VMs. I don't have the details to hand at the
> moment, but KVM was superior to both. PV drivers where applicable. I
> have been running KVM for about 15 months now, with 30 VM's on one
> host and 38 VM's on another. It has been solid; no problems, but
> unfortunately I had
> problems with Xen.

And Xen has been rock solid on my production systems.
So it depends :)

-- Pasi