> * Li, Liang Z (liang.z...@intel.com) wrote: > > > > Hi David, > > > > I remembered some guys wanted to solve the issue of post copy recovery > when network broken down, do you know latest status? > > Hi Liang, > Yes, Haris looked at it as part of GSoC, the latest version is what was > posted: > > https://lists.nongnu.org/archive/html/qemu-devel/2016-08/msg03468.html > > I've not done any work on it since then; there are a couple of hard problems > to be solved. The simpler is making sure that we always correctly detect a > migration error due to networking (rather than some other non-recoverable > error); there's lots of migration code that doesn't check for a file error > straight away and only hits the error code later on when it's too late to > recover. > > The harder problem is that we often end up with the case where the main > thread is blocked trying to access postcopied-RAM, e.g. an emulated > network driver tries to write an incoming packet to guest RAM but finds the > guest RAM hasn't arrived yet. > With the main thread blocked it's very difficult to recover - we can't issue > any > commands to trigger the recovery and even if we could we'll have to be very > careful about what things those commands need the main thread to do. > > Dave
Thanks for your information! I will take a look first, maybe get back to you later. Liang
