anup at brainfault
May 5, 2012, 7:24 AM
Re: [Android-virt] [ANNOUNCE] Xvisor ARM better than KVM ARM in CPU virtualization
I agree we cannot predict real world performance based on performance on
ARM fast models but if system A is performing better than system B no ARM
fast model or QEMU then in real world system A will perform better than
system B. Of-course in real world scale of difference in performance
between system A and system B will differ.
The previous announcement only proves that Xvisor ARM is relatively better
than KVM ARM.
On Sat, May 5, 2012 at 3:36 PM, Peter Maydell <peter.maydell [at] linaro>wrote:
> 2012/5/5 Anup Patel <anup [at] brainfault>:
> > This announcement is to show an apple to apple performance comparison
> > between Xvisor ARM and KVM ARM running on VExpress-A15 Fast Model.
> I would strongly caution against trying to do any performance/timing
> type tests if you're still running on the ARM Fast Model -- they are
> not representative of performance characteristics on hardware
> and you really can't draw any conclusions about real world
> performance by timing things on a model. It's quite easy to get
> into a situation where all you're measuring is "does my code happen
> to do a lot of some perfectly reasonable operation which happens
> to be hard and slow to implement for the model?".
> (Also, KVM for ARM is still under development and we haven't
> yet made several of the obvious performance improvements like
> in-kernel irqchip and timer support, so it's not really a very
> useful thing to compare against yet.)
> -- PMM