Re: [PATCH RFC 04/15] KVM: Implement ring-based dirty memory tracking

Paolo Bonzini
2019-12-10T13:32:04Z

On 10/12/19 14:25, Michael S. Tsirkin wrote:
>> There is no new infrastructure to track the dirty pages---it's just a
>> different way to pass them to userspace.
> Did you guys consider using one of the virtio ring formats?
> Maybe reusing vhost code?

There are no used/available entries here, it's unidirectional
(kernel->user).

> If you did and it's not a good fit, this is something good to mention
> in the commit log.
>
> I also wonder about performance numbers - any data here?

Yes some numbers would be useful. Note however that the improvement is
asymptotical, O(#dirtied pages) vs O(#total pages) so it may differ
depending on the workload.

Paolo