[comp.sys.mac.system] Turning off time slices in S7READ/NEXT

umh@vax5.cit.cornell.edu (06/03/91)

In article <1991Jun1.070626.2853@spool.cs.wisc.edu>,
tonyrich@titanic.cs.wisc.edu (Anthony Rich) writes: 
> Larry Rosenstein writes:
> 
>> It is straightforward to write a program that sends a quit Apple event to
>> all running apps (including the Finder) and then launches [a time-critical]
>> app such as Tetris [...].
> 
> OK, but what about killing live background extensions like SuperClock that
> aren't "launched apps" in the usual sense?  Maybe they shouldn't be "killed",
> just "put on hold" until the time-critical foreground app is finished.
> INITs/CDEVs shouldn't be killed, then require manual re-launching later.
> 
> Glenn Austin writes:
> 
>> Well, considering the foreground application has control over when
>> the application is switched out, [switchouts] shouldn't be a problem.
> 
> As I understand it, an app has control over *when* it's switched out, but not
> for *how long*--so I don't think cooperative multitasking solves the problem.
> It's considered "Multifinder friendly" for an app to give up the CPU once
> in a while so that other tasks like modem downloads don't timeout.  The hard
> part for a time-critical app is getting the CPU *back* quickly enough.
> 
> An interesting solution might be to have separate foreground and background
> processors.  That way, the foreground app wouldn't need to be interrupted
> to handle the background stuff.  If a user interface should give the user
> the illusion that the computer is always paying attention, why not dedicate
> a processor to maintaining that illusion?

And this brings us into the brave new world of multithreaded programs and real
operating systems. Since, as we all know, Apple is devoting substantial company
resources to their new, non-Mac machine to be released at the end of '92 (yeah
sure, we all think Apple will stick to a schedule :-) ), it would seem to me
far more sensible to devote effort to creating a decent OS from scratch than
patching an existing mess. Thus my conclusion is that we are never going to see
this on Macs.

Anyone know what the new OS will be? My choice would be to use a Mach kernel to
stop wasting time and get a real OS right away, then add object oriented
extensions from PenPoint to that, plus a final Mac compatibility box+ Toolbox
ala AIX on that. I guess we Mac users will become like Apple II users- never
abandoned by Apple, and with our own weak programs that perform as well as the
hardware will allow, but destined for extinction in 10 years.

Maynard Handley

scasterg@magnus.acs.ohio-state.edu (Stuart M Castergine) (06/03/91)

In article <1991Jun3.015035.5222@vax5.cit.cornell.edu> umh@vax5.cit.cornell.edu writes:

>And this brings us into the brave new world of multithreaded programs and real
>operating systems.

Sigh. Another "what a terrible operating systeem is MacOS" message. :-)

 Since, as we all know, Apple is devoting substantial company
>resources to their new, non-Mac machine to be released at the end of '92 (yeah
>sure, we all think Apple will stick to a schedule :-) ), it would seem to me
>far more sensible to devote effort to creating a decent OS from scratch than
>patching an existing mess. Thus my conclusion is that we are never going to see
>this on Macs.
>

That certainly sounds possible.


>Anyone know what the new OS will be? My choice would be to use a Mach kernel to
>stop wasting time and get a real OS right away,

Oh yes, by all means, a _real_ OS. I'll have to get over the enjoyment
of my fantasy OS, tho. :-)

I don't know Mach and I have a doubt that Apple will ever build its
main consumer OS on Unix, so I can't postulate what the next OS will
be. Maybe it won't be a "real" OS. Maybe another make-believe OS! Most
likely, it will be built from the ground up, not based on any existing
system. 

 then add object oriented
>extensions from PenPoint to that, plus a final Mac compatibility box+ Toolbox
>ala AIX on that. I guess we Mac users will become like Apple II users- never
>abandoned by Apple, and with our own weak programs that perform as well as the
>hardware will allow, but destined for extinction in 10 years.
>

I guess I'm just a realist. No computer lasts forever. If the
Macintosh line as we know it today is not essentially extinct in 10
years, I will be mighty surprised. The Macintosh has only been
available as a commercial product for eight years, and already the
older machines in the line are in exactly the situation described
above "... never abandoned by Apple, and with our own weak programs
that perform as well as the hardware will allow..."

That's just the way things are and will be. There's not a computer
company on earth that can avoid this (or wants to, probably). :-)

>Maynard Handley
>
>


-- 
scasterg@magnus.acs.ohio-state.edu	Stuart M Castergine
 "The thought of failure never occurs to me." -- Evaine
 "Anybody who does as many stupid things as she does
  ought to be dead!" -- Ingmar

rgonzal@elbereth.rutgers.edu (Ralph Gonzalez) (06/04/91)

I'm certainly not an expert on operating systems, but I don't see why
you have to trash the entire Mac OS just so you can play games
uninterrupted.  How about a simple patch like a new Toolbox routine
called "give up cpu but get it back as soon as possible"!?  Then if
your other apps support the routine they will avoid using more cpu
cyles than they absolutely need to stay alive.

-Ralph
(rgonzal@elbereth.rutgers.edu)