Virtualization Changes in 2.6.21

James Bottomley has a byline article in the June Enterprise Open Source Magazine.  A synopsis is below:

Back in July 2006, one of the most contentious issues at the Linux Kernel Summit was what to do about virtualization. At that time, there were three contenders: Xen, VMware, and OpenVZ (the latter being a lighter-weight container-based approach). The biggest fight was between Xen and VMware over competing approaches to running kernel operations through their respective hypervisors: Xen touting their hypercall interface and VMware touting their VMI (Virtual Machine Interface) approach. Neither of these approaches was palatable to kernel developers for a variety of reasons, most of which were technical but also because selecting either would give that contender a great public relations boost over their competitor.