Re: [Qemu-devel] [RFC Design Doc]Speed up live migration by skipping free pages

[Paolo Bonzini]

On 24/03/2016 16:16, Li, Liang Z wrote:
> > There's no guarantee that there's a single 'hole'
> > even on the PC, and we want balloon to be portable.
> 
> As long as we know how many 'hole' and where the holes are.

The mapping between ram_addr_t and GPA is completely internal to QEMU.
Passing it to the guest is a layering violation.

Paolo

> we can filter out them. QEMU should have this kind of information.
> I know my RFC patch passed an arch specific free page bitmap is not
> a good idea. So in my design, I changed this by passing a loose free page
> bitmap which contains the holes, and let QEMU to filter out the holes
> according to some arch specific information. This can make balloon be 
> portable.
>