Comment 4 for bug 612671

Further experimentation on this from building a brand new XP SP2 VM then upgrading it to SP3 and performing migrations seems to be a little better, but not perfect.

A migration from node 1 to node 2 (in any order) works for the 1st migration. If a 2nd migration is tried then when it arrives at the back at the original node (i.e. node 1 -> node 2 -> node1) the VM is frozen (hung). CPU usage for the VM process is pegged at 100%.

I tried switching the CPU emulation to i686 from x86_64 - this was based on a posting about XP VMs locking up but that does not seem to have made any difference.

However, if I have a 'long' delay between migrations (> 30 minutes in what I tried) the migration back /does/ seem to work. This has happened a couple of times, but I've not found out how long the VM needs to be on node 2 before it can successfully migrate back to node 1 (i.e. I tried 30 minutes but that was not specifically chosen as a time to wait).

I'm not sure if the wait works in absolutely every case - I'll need to try more experiments. If there are any suggestions on what I can do to help get the cause identified & fixed, let me know.