Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!decwrl!pa.dec.com!bacchus!mwm From: mwm@raven.relay.pa.dec.com (Mike (My Watch Has Windows) Meyer) Newsgroups: comp.sys.amiga.misc Subject: Re: True Multitasking Message-ID: Date: 18 Jan 91 20:35:32 GMT References: <1991Jan11.075022.16943@zorch.SF-Bay.ORG> <1991Jan11.081137.17529@zorch.SF-Bay.ORG> <1991Jan18.055614.13889@zorch.SF-Bay.ORG> Sender: news@pa.dec.com (News) Organization: Missionaria Phonibalonica Lines: 71 In-Reply-To: mykes@zorch.SF-Bay.ORG's message of 18 Jan 91 05:56:14 GMT In article <1991Jan18.055614.13889@zorch.SF-Bay.ORG> mykes@zorch.SF-Bay.ORG (Mike Schwartz) writes: In article mwm@raven.relay.pa.dec.com (Mike (My Watch Has Windows) Meyer) writes: >[Still trying to push this back to comp.sys.amiga.misc - mwm] > >In article <1991Jan11.081137.17529@zorch.SF-Bay.ORG> mykes@zorch.SF-Bay.ORG (Mike Schwartz) writes: > There must be 2 kinds of tasks possible in a "true" multitasking system. > One kind of task is the kind that Amiga and Multifinder support, multiple > applications. The second is one that multifinder does not support which > is a task that is part of an application and is spawned while the > application runs and terminates sometime before (or right when) the > application quits. > >The only thing interesting you might be talking about is lightweight >processes. The only reason those are interesting is because they're >cheaper than normal processes. In any case, they have nothing to do >with the topic at hand. It has everything to do with the discussion at hand. Without what you call lightweight processes, you have something less than what you have with them. Without lightweight processes, you DON'T HAVE true multitasking. Boy, are the Unix people going to be surprised when you try and tell them they don't have "true" multitasking - whereas the Amiga, which isn't even a "real" computer, does. True multitasking is what the posting was about that this response was made to. Yes, but you obviously have no idea what is meant by that phrase. Lightweight processes allow you to have a second task that writes graphics to the screen while another manipulates pulldown menus. Lightweight processes allow a hard disk backup program to read from hard disk, compress, and write to floppy (that is 1 application plus 2 lightweight processes) in the most efficient manner possible. It allows applications to take advantage of the multitasking environment. Neither of these require lightweight processes. The latter one doesn't require multitasking _at all_ - you can do it with co-routines and asynch IO. The latter requires multitasking by definition (you required two processes), but can be done with cooperative multitasking - which means it could be done with co-routines inside one task. Call me an anal retentive amiga user because I am one. Actually, I don't think you're anal retentive; that usually implies a obsession with getting things exactly right, which you don't show. This thread is not just a bunch of Amiga guys having an intelligent discussion about various kinds of multitasking. It is Amiga guys explaining the difference between TRUE multitasking, which the Amiga has, and a switcher (albeit a glorious one) which the Mac has. No matter what we (Amiga) say, they (Mac) don't wanna believe that what they have is any less than what we have. You still don't know what you're talking about - but this time it's because you jumped into the middle of a conversation without trying to understand it. This conversation is a few Amiga owners trying to improve the image of _all_ amiga owners by getting them to drop the inflammatory phrase "true multitasking" in favor of the technically more accurate phrase with prior usage - "preemptive multitasking". Iny our specific case, I'd recommend the practice of understanding what you're going to talk about before you start.