On Mon, Nov 08, 2021 at 09:07:51PM +0000, David Matlack wrote: > On Fri, Nov 05, 2021 at 06:17:11PM +0100, Janis Schoetterl-Glausch wrote: > > On 11/4/21 23:45, David Matlack wrote: > > > > [...] > > > > > > The last alternative is to perform dirty tracking at a 2M granularity. > > > This would reduce the amount of splitting work required by 512x, > > > making the current approach of splitting on fault less impactful to > > > customer performance. We are in the early stages of investigating 2M > > > dirty tracking internally but it will be a while before it is proven > > > and ready for production. Furthermore there may be scenarios where > > > dirty tracking at 4K would be preferable to reduce the amount of > > > memory that needs to be demand-faulted during precopy. > > Oops I meant to say "demand-faulted during post-copy" here. Sorry to join late, but this does sound like an interesting topic, too. Hopefully assuming postcopy will be enabled in just a few iterations of precopy, write amplification could hopefully be a much smaller problem, so the mostly-static pages can still be successfully migrated during precopy. Please share more information when there is, and I'll be very interested to learn. Thanks! -- Peter Xu
