Virtualization: Concepts, Applications, and Performance Modeling

Virtualization was invented more than thirty years ago to allow large expensive mainframes to be easily shared among different application environments. As hardware prices went down, the need for virtualization faded away. More recently, virtualization at all levels (system, storage, and network) became important again as a way to improve system security, reliability and availability, reduce costs, and provide greater flexibility. This paper explains the basics of system virtualization and addresses performance issues related to modeling virtualized systems using analytic performance models. A case study on server consolidation is used to illustrate the points.