Hi Peter, As we discussed in LC3 China, the current scheme of "migration to file" can't fit on production environment, which will cause the snapshot file bigger and bigger when the guest is under enough memory pressure. We can't assume what size the snapshot file is. Pls have a look if we have a simple method to resolve the problem. :)
PS: the below link is zhanghailiang's scheme based on userfaultfd. https://lists.gnu.org/archive/html/qemu-devel/2016-01/msg00664.html Thanks, -Gonglei
