Xen vs. KVM yet again

Interesting read on Baremetal vs. Xen vs. KVM benchmark

In short: Xen with HVM guests + PV drivers (that is, full virtualization mode with paravirtualised drivers, as opposed to paravirtualized mode) and KVM are equally effective. In some tests one was marginally faster, in some tests it was the other.

If you read my old posts, I was in favor of Xen for better performance of its PV (paravirtualized) guests and ability to run on older CPUs. Today all my boxes have hardware support for virtualization and I don't even use PV mode. While it's still slightly faster, it's not worth the additional complexity. If you've ever had a VM that failed to boot when PyGrub couldn't find the right kernel, you know what I mean. HVM + drivers/tools, that's the way to do it on any platform - be it Xen server or Virtualbox on a desktop.

Even shorter: virtualization platforms are so mature there's no real difference in performance or stability. For large installations, advanced features and management tools are the important factors. For one machine - familiarity and ease of use.