Path: utzoo!utgpu!watserv1!watmath!att!pacbell!pacbell.com!mips!apple!usc!cs.utexas.edu!uunet!cbmvax!jesup
From: jesup@cbmvax.commodore.com (Randell Jesup)
Newsgroups: comp.arch
Subject: Re: Macintosh OS
Message-ID: <12189@cbmvax.commodore.com>
Date: 3 Jun 90 08:48:48 GMT
References: <402@newave.UUCP> <3300131@m.cs.uiuc.edu> <5031@quanta.eng.ohio-state.edu> <1990May28.083518.26003@laguna.ccsf.caltech.edu> <54992@microsoft.UUCP>
Reply-To: jesup@cbmvax (Randell Jesup)
Organization: Commodore, West Chester, PA
Lines: 22

In article <54992@microsoft.UUCP> edwardj@microsoft.UUCP (Edward JUNG) writes:
>The thing that pre-emptive multitasking does is give guarantees against poor
>code.  The Macintosh (and Windows) have gained alot of mileage with cooperative
>multitasking (note that this does not apply to ALL Windows apps) solely because
>their apps give up time relatively frequently.  Even so, any single misbehaved
>application in the background can utterly destroy the preformance of a correctly
>written application in the foreground.

	Note that in this case, "poor code" can mean anything that runs for
a signifigant period without explicitly giving up the processor.  This includes
most "standard" C programs which use appreciable processor time, such as
ray tracers.  It also means that background tasks doing IO may not work well
or at all if the frontmost application doesn't give up the cpu VERY often,
since various buffers may overflow, etc.

disclaimer: I'm biased, of course, since I maintain a pre-emptive MT OS on a
personal computer.

-- 
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.cbm.commodore.com  BIX: rjesup  
Common phrase heard at Amiga Devcon '89: "It's in there!"