Virtualization, Isolation and Emulation in a Linux Environment

Virtualization has received much attention the past few years. However, it is anything but new, as one of the first implementations were done in the 1960s to create a multi user system by running multiple instances of a single user operating system. Virtualization mechanisms have evolved much since that time, and an ever increasing number of similar technologies have been collected under the virtualization concept. This thesis begins by exploring the history and theoretical foundation behind traditional virtualization, and carries on by studying various virtualization technologies that do and do not fit into this definition. Next, it tries to answer the question that many organizations ask themselves: Which virtualization technology is the best one? While the question can be answered for a certain application at a certain time, the general answer will for some time be that it depends on the problem at hand and what demands that exists for the technology, e.g. memory footprint, I/O performance, etc. The results from a series of generalized benchmarks is presented in order to enlighten the problems that exist with virtualization. In addition to plain virtualization, common management tools for both the physical and virtual machines, with a natural weight on the virtual machines, is explored. By using a common management technology, the selection of virtualization technology need not be limited to a single technology.