Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!gatech!gtss!chas
From: chas@gtss.gatech.edu (Charles Cleveland)
Newsgroups: comp.sys.amiga
Subject: Re: simple multitasking examples
Message-ID: <333@gtss.gatech.edu>
Date: 14 Feb 89 00:17:12 GMT
References: <8662@louie.udel.EDU>
Reply-To: chas@gtss.UUCP (Charles Cleveland)
Organization: Georgia Tech School of Physics
Lines: 44

Multitasking is great, but it shouldn't be necessary to resort to AREXX
or TCP/IP server stuff to demonstrate clearly.

So I thought, what about just using one of the process monitors, like
SysMon (from ASDG, I think), or pm, or whatever?  Especially the graphical
ones, although some PC'ers might like a table generator instead, not being
used to a 'graphical' interface ;-).  Doesn't one of these maybe even come
with 1.3?  Just a minute while I check, using methods more or less easily
simulated, but not duplicated, on an MSDOS machine.... Why yes, right here in
the Tools directory of my "Extras 1.3" disk is something call PerfMon.

It's just another program.  It runs with every other piece of software that
doesn't take over the machine.  You can use it to show how two *other* pieces
of software can *share* the CPU.  And nothing like it has ever been dreamt
of in the MSDOS world because it has no relevance there.  The mere existence
of such programs is a clear sign that the Amiga really multitasks.  And all
us UNIX folk take it so much for granted that we don't think to mention it.


So.  Do I win the prize?  Or do the IBMers just say it can all be done with
interrupts?  I suspect it can.  Perhaps it even is.  But the real advantage
of a multitasking operating system is that you don't have to do it; it gets
done for you.  You don't have to worry about whether your interrupts are
compatible with some other programmer's, who is probably a real dickhead.
You just get your turn.

One other thing you could point out to them, which might floor an IBMer.  If
the CPU has no instructions to execute, the OS STOP's it, until there are.
This clears the bus for the special purpose chips, or other 'peripherals'.
How much work does a PC get done with its CPU turned off?  It a way, this is
the ultimate in multitasking, perhaps relating more to parallel processing
instead.  Which of course, brings to mind the 2000 and its capacity to
simultaneously utilize the 80xx on the IBM side and the 680xx on the Amiga
side.  But I don't know enough about that to comment on it.  But it's got to
be a hell of a lot easier to do here than it is in an MSDOS box with a
limited number or interrupts to work with, and with everyone having their
own, possible ill-conceived and certainly not necessarily well-coordinated,
ideas of how to use them.

-- 
-  It is better for civilization to be going down the drain than to be  -
-  coming up it.                                        -- Henry Allen  -
Charles Cleveland  Georgia Tech School of Physics  Atlanta, GA 30332-0430
UUCP: ...!gatech!gtss!chas                INTERNET:  chas@gtss.gatech.edu