Il 18/02/2014 11:38, Michael S. Tsirkin ha scritto:
What if you detach and re-attach? Is it fast then? If yes this means the issue is COW breaking that occurs with get_user_pages, not translation as such. Try hugepages with prealloc - does it help?
I agree it's either COW breaking or (similarly) locking pages that the guest hasn't touched yet.
You can use prealloc or "-rt mlock=on" to avoid this problem. Paolo
