Hi Eric,
Sorry to hijack this thread.
Have you used vcpu_quota in production? I have come across a CPU stall problem when vcpu_quota is effective not long ago and I'm still looking for an answer.
For example, when I set
virsh schedinfo <id> --set vcpu_quota=5000
Then no matter the vm is loaded or idle, in about two weeks, sometimes sooner, the vm will have CPU stall in dmesg log. The CPU stall problem makes system not responsible and results in network failure, i.e. ping and ssh will fail. I have tried a few guest distro (ubuntu, CentOS, debian) with different kernel version (3.2, 3.8) and they all have this problem.
Do you have any idea what's behind the scenes?
The software I am running:
hypervisor os: ubuntu 12.04.3
hypervisor kernel: 3.8.0-35-generic
vm os: ubuntu 12.04 // I have tried other OSes.
vm kernel: 3.2.0-56-virtual
libvirt: 1.1.1-0ubuntu8~cloud2