[libvirt-users] monitoring kvm machines with libvirt

Hey folks. Currently, i am working on my bachelorthesis. Subject of this thesis is to setup an accounting-solution for the Private Cloud with Eucalyptus. Eucalyptus works with libvirt providing kvm instances. my question is, if i can grep facts like general uptimes, cpu-peaks and disk i/o of each vm with libvirt-tools?! I just found one called virt-top, which monitors each vm, but unfortunately it produces to much overhead. If you should be no tool, can anybody give me a hint, where i best look at to grep these facts? First try is to grep the uptime of each vm by writing a little deamon, checking one time per minute via virsh, if the vm is in state running. But i don't know, if this is best. thanks for your support! cheers, Karsten