Both the kernel kvm and user-space qemu support SystemTap probes. These are some examples using those probe points to gain a better understanding of where the performance problems exist in virtualization system. Information about the qemu tracing points is at: http://wiki.qemu.org/Features/Tracing For more information about SystemTap: http://sourceware.org/systemtap/ These examples may or may not work in your particular evironment. Feedback about the examples would be appreciated. Please comment about them on systemtap@sources.redhat.com. -Will Cohen