On 19.06.2012, at 23:13, Benjamin Herrenschmidt <b...@kernel.crashing.org> wrote:
> On Tue, 2012-06-19 at 23:00 +0200, Alexander Graf wrote: >> How is the problem different from RAM? It's a 16MB region that can be >> accessed by the guest even during transfer time, so it can get dirty >> during the migration. But we only need to really transfer the last >> small delta at the end of the migration, right? > > Because with -M pseries it's not mapped into guest space but instead is > a chunk of physically contiguous memory accessed directly in real mode > by KVM. So no dirty tracking here. > > We could keep track manually maybe using some kind of dirty bitmap of > changes to the hash table but that would add overhead to things like > H_ENTER. Only during migration, right? Alex
