Virtual Machines

Chapter Eight System Virtual Machines

It was observed very early that many of the hardware resources in a typical computer system are underutilized. The concept of time sharing was developed to improve resource utilization by allowing multiple users to access a single computer system simultaneously, with each user being given the illusion of having access to a full set of system resources. In order to create this illusion, a multiprogramming operating system essentially implements a process virtual machine for each application-level program and switches resources among the programs on a time-shared basis.

System virtual machines take this concept one step further by providing a similar illusion for complete systems. A system VM environment ...