On 06/16/10 - 11:02:01PM, Zhang Qian wrote:

Hi,

I have someVMs in my KVM hosts(RHEL 5.5), I found when run "virsh save <domain> <file>" to save a VM, the command "virsh dominfo <domain>" will hang until the save command finishes. Is this libvirt's behavior? Or KVM/QEMU's? This may impact the performance.

This is a bug in libvirtd itself, in that the threading wasn't properly unlocking all of the time. So the save command would take a lock for the duration of the command, and all other commands would queue up behind it. Recent work in libvirt should have mostly eliminated this phenomenon; you'll want to try out libvirt 0.8.1 or later. -- Chris Lalancette