Hi Guys, I finally have had some strange problem with my haswells This occur with live migration only, with a specific workload. I have a java application, which use normally 1 core of 16 vcpus. After a live migration, for the same workload, it's jumping to 16cores usage, 1600%. (no dmesg error, no iowait, ....) I can't reproduce it with simple cpu or memory benchmark. This is with pve-kernel 3.10 on the host and debian 3.16 kernel on guest. Using pve-kernel-4.2 fix the problem. So it's a kvm bug.