Re: PCI passthrough with VT-d - native performance

Ben-Ami Yassour
2008-07-16T16:13:42Z

On Wed, 2008-07-16 at 10:23 -0500, Anthony Liguori wrote:

>
> What about virtio?
didn't try it yet.

> Also, which emulated is this?
the default

>
> That CPU utilization is extremely high and somewhat illogical if native
> w/vt-d has almost no CPU impact. Have you run oprofile yet or have any
> insight into where CPU is being burnt?
>
> What does kvm_stat look like? I wonder if there are a large number of
> PIO exits. What does the interrupt count look like on native vs. KVM
> with VT-d?
>
> Regards,
>
> Anthony Liguori
>

These are all good points and questions, I agree that we need to take a deeper
look into the performance issues, but I think that we need to merge with
the main KVM tree first.

Regards,
Ben