In computing, native virtualization is a virtualization technique that presents a software virtual machine by leveraging hardware-based Virtualization Technology supported by some CPUs. This improves upon paravirtualization and full virtualization by reconciling many of the performance and management challenges.

It is most similar to full virtualization in that it supports a partitioned server running disparate guest operating systems “as is.” This includes support for 32- and 64-bit applications and operating systems running concurrently. But native virtualization uses AMD’s and Intel’s processor virtualization technology to decrease virtualization overhead. It does not rely on binary translation to emulate non-virtualizable x86 instructions, but instead uses hardware virtualization assistance on new processors to permit each guest OS to run in “ring 0” and run at full processor speed. In native virtualization, the hypervisor runs in a new privilege ring sometimes referred to as “ring -1” or “ring minus one”.

Implementations

For a list of virtualization software that makes use of hardware-based Virtualization Technology, see Virtualization Technology software.

Benefits

Native virtualization preserves investment in current certified software stacks by supporting unmodified legacy operating systems. This eliminates the need to upgrade to the latest operating systems in order to run on the latest hardware. The removal of a complete host OS greatly simplifies maintenance and management since there is no host OS or virtualization software to install, patch, upgrade and maintain. Native virtualization is based on hardware assistance and leverages both the new "minus 1" privilige level for the execution of hypervisor code and the new virtualization instructions to manage virtual machine state transitions. This approach is very efficient since it does not use binary translation and runs all guest operating systems in ring 0, eliminating expensive ring transistions from other rings to ring 0.

See also

• x86 virtualization

Virtualization software