Notes on Xen

This is a high level view of the Xen virtual machine technology. Their virtual machines come in two flavors:
Paravirtualization
which is a virtual machine with modified privileged architecture that is more efficient and does not depend on special Intel and AMD features that were added to overcome design deficiencies in early x86 designs.
HVM
which is full virtualization.
The performance advantage of paravirtualization is very sensitive to the hardware architecture and is most significant on x86. The Xen page is silent about whether the full virtual machine has the “special hardware”. I speak here of what they call HVM which is the full virtualization path.