Yes, they are special, but...

[barmar@THINK.COM]

   Are you saying the hardware can in fact run multiple address spaces?
   I have no argument or fixed belief to the contrary, but I've certainly
   never heard anyone say that.

Any machine with virtual memory can run multiple address spaces.  All
you need is code to change the memory mapping parameters.

   But the point I was really making is not that timesharing improves
   performance, but that it improves *functionality*.  It's essentially
   impossible right now to use a LispM over a dialup; not that I would
   want to do so very often, or for very long at a time, but there are
   those occasions when it sure would be handy.  I know, I know, multiple
   address spaces and scheduling across page faults are not absolute
   requirements for that by any means.  But they do make it work better.
   And anyhow, as you acknowledge, they are the kind of thing the
   workstation culture expects.

I don't understand how process switching during page faults relates to
using dialups AT ALL.  Assuming it improves performance, it will do so
whether or not you're using a dialup.  Is multi-process performance
only an issue when you're using a dialup?

Even if you do this, what Genera needs much more to make dialup use
reasonable is decent software to run on the dialup stream, e.g. a
character-oriented text editor, and a way to interrupt a process.