I'm wondering under what circumstances the kvm-clock source is exposed to a guest. I've got a bunch of KVM servers running Centos 5.5 and some of the guests have are defaulting to jiffies or apic whilst some are picking up kvm-clock. These guests are a mix of 32bit and 64bit Centos 5.5. Looking at the virtual machine definition file there doesn't appear to be a difference between the guests with kvm-clock and those without. Any where else to look, or what configuration will expose kvm-clock to a guest. Steve -- Steven Ellis - Bulletin.Net Inc - http://www.bulletin.net