[ih] vm vs. memory

[johnl at iecc.com (John Levine)]

In article <593e3d78-5af7-e30b-a1ae-ad875ddee643 at gmail.com> you write:
>I disagree with that evaluation. It started in practice with the
>famous "one-level storage system" paper from Manchester**, with the
>specific goal of making a small high-speed memory look like a much
>larger one. I don't think it was viewed as a work-around, but rather
>as a brilliant engineering solution to the high cost of high-speed
>memory, vastly easier to use than explicit overlays.

But it was a workaround, albeit a much nicer one than explicit
overlays (this I know, having done digital origami with overlay
loaders.)  What they really wanted in both cases was enough RAM to run
the program.  Since they didn't, they had various kludges to fake it.

VM stopped being a workaround when people realized that you could use
the same hardware to unify RAM and disk files.  It didn't take long,
Multics was doing that by 1966 and TSS/360 (badly) in 1967.

R's,
John