Virtual micromachines (Whatever happened to milliprocessors)

The main point of this note is a rather obvious one: The notion of virtual computer systems applies to many levels (macro-, micro-, nano-, pico-, etc.) of processors and associated units as well as to conventional data processing systems. Since these processors and units of whatever level all include the same basic notion of computation, we have come to use the term computational theater to represent the idea of a formally described processing system, independent of the level of processing. Self-virtualizability is not a likely property of today's microprocessors; however, the current trend toward user visible microprogramming may be expected to influence the architecture of microprocessing systems in ways that will lessen the difficulty of implementing a virtual microprocessing capability. This point is discussed below.