🚀 go-pugleaf

What's all this about NEEDING memory segmentation for Multitasking. You can
have Multitasking without memory segmentation. (Of course memory segmentation
helps a lot). Just look at several multitasking OSs for the ST, all running
without a REAL MMU: OS-9/68000, IDRIS, RTOS-UH/Pearl, MINIX-ST, Xinu,
(what else ?).

Of course, forking processes becomes slow, but not impossible (see MINIX-ST).
Also, one of your tasks may clobber another any time by writing into it's
memory (but that's more a problem of coding).

Multitasking essentially is the sharing of one major resource in a computer,
namely the CPU, among several processes by switching the process currently
running rapidly between several processes ready to run at the given moment,
thus making it appear as if each of these processes were being executed
concurrently. If you have the so-called round robin scheduling mechanism,
each ready process gets a time slice, and the more processes there are ready
to run, the fewer time slices each of them gets, so they apparently execute
slower and slower, the higher the load climbs.

Multitasking as such has nothing to do with memory protection (which is why
Xinu can be made to run on an LSI/11 [see D. Comer: Operating system design,
the XINU approach]).

I hope this convinces everybody that multitasking is possible (even if not
feasible due to lack of speed) on the ST.

Martin

PS: Everything I said above really only (barely) scratches the surface  of
    the matter.

Disclaimer: All of the above is my on opinion and does not express opinions
	    or company policy of my employer.
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