On 01/12/2015 16:02, Andrea Arcangeli wrote: > > Applying your technique to non-leaf shadow pages actually makes this > > series quite interesting. :) Shadow paging is still in use for nested > > EPT, so it's always a good idea to speed it up. > > I don't have the full picture of how userfaultfd write tracking could > also fit in the leaf/non-leaf shadow pagetable write tracking yet but > it's good to think about it.
It's unrelated. Xiao wrote this series for KVM-GT. I'm suggesting that he uses userfaultfd write tracking (or similar techniques---but anyway implemented out of KVM) for KVM-GT. The benefit is that KVM-GT is then unrelated to KVM, similar to legacy KVM device assignment vs. VFIO. However, he also applied this new API to shadow pagetable write tracking. He gets measurable (~2%) performance improvement. We can look separately at how to get a similar performance improvement, even if KVM-GT will not use the new page tracking API. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html