Information Technology Reference
In-Depth Information
technologies draw heavily on the concepts, architecture, and even the language
invented in relation to the early hypervisors.
The economic incentives for virtualization have evolved since server virtualiza-
tion was invented. Originally, it helped avoid mainframe acquisition costs by shar-
ing a single computer among many virtual machines (or conversely, amortizing its
expense over their combined workloads) in circumstances where an individual
computer was extremely expensive. Today, server virtualization is used to reduce
environmental and license costs resulting from server sprawl, and to consolidate
the load from under-utilized computers whose individual costs are low. While they
seem to be very different, these issues are actually opposite sides of the same coin.
Both yesterday and today, substantial benefits can be obtained by reducing the
number of physical servers, and virtualization is a powerful tool for turning that
goal into a reality.
