Technology/VMs, (sdf.org), 02/19/2019
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I just read the oldest reference to "virtual machines" that
I know of, dating back to a technical report for DARPA in
1975[1]. Of course, I know very little about the history of
virtual machines and/or emulation, and I came across the
reference by accident while searching for other information.
I know enough to realize that the term "virtual machine" has
come to have a particular definition that may not match the
one used here; still, it was interesting to read, and so
I've copied the reference paragraph below (from page 14 of
the document):
"The PRIM (Programming Research Instrument) project has
completed an interactive microprogramming facility to be
used as a general-purpose emulation laboratory for creating,
manipulating, and debugging arbitrary computer architectures
and high-level language processors. A unique service on the
ARPANET, it consists of a powerful sharable micro-
programmable CPU (the MLP-900) closely coupled with a TENEX
system and appropriate software to allow interactive access
to, and control of, the computing environment the user
wishes to emulate. The MLP-900 has proved to be reliable
in continuous operation since August 1974, with the primary
appications being the emulation of existing minicomputers
for experimentation and evaluation. A library of emulators
is being developed as user population grows; the library
currently consists of a basic PDP-10 (developed as a test
vehicle for the system), a PDP-8, a PDP-11, an AN/UYK-20, a
Univac 1050 MOD2, and a Nova (CPU only). As the emulator
library continues to grow, the PRIM facility should become
more attractive to a larger user community. Current plans
also include allowing users access to these virtual
machines (emulators) via a National Software Works Tool
Bearing Host. This will make available several new NSW tools
with a single interface. (See Section 3 for a further
discussion of the National Software Works (NSW).) PRIM is
therefore becoming a service facility, providing a unique
tool to groups of NSW programmers, as well as an
experimental computer environment for the researcher."
[1]
https://apps.dtic.mil/dtic/tr/fulltext/u2/a016662.pdf
