Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!agate!darkstar!ucscb.UCSC.EDU!davids
From: davids@ucscb.UCSC.EDU (Dave Schreiber)
Newsgroups: comp.sys.amiga
Subject: Re: Multitasking is slower
Keywords: games, multitasking
Message-ID: <4108@darkstar.ucsc.edu>
Date: 5 Jun 90 22:51:31 GMT
References: <279@smosjc.UUCP> <4039@darkstar.ucsc.edu> <1990Jun5.082227.29350@agate.berkeley.edu>
Sender: usenet@darkstar.ucsc.edu
Organization: UCSC Open Access
Lines: 40


In article <1990Jun5.082227.29350@agate.berkeley.edu> laba-1ei@e260-3c (Joseph Chung) writes:
>In article <4039@darkstar.ucsc.edu> davids@ucscb.UCSC.EDU (Dave Schreiber) writes:
>>>NO!  For a program to allow multitasking, it has to be "nice".  It must own
>>>and disown the system resources (esp. blitter) using OS calls, and do so
>>>often enough to allow other tasks a chance to use them.  Depending on the 
>>
>>Are you reading all of the original message?  If the machine is in a state
>>so that the game is going "without anything else running", then there won't
>>be "other tasks" that demand system resources like the blitter.  This
>>seems fairly self-evident.
>
>Hold on a minute.  If I want to multitask,  I must nicely ASK for resources
>to be given, therefore incurring an extra overhead.  However, if I take over
>the machine, I TAKE whatever resources I want, bypassng the boss.

Hmmm.  Perhaps someone from Commodore could answer this:  how much
overhead does the OwnBlitter() function take?  Will there be a 
signifigant increase in speed if a program gets the blitter for the
entire duration of the program, as oppossed to getting it, releasing
it, getting it, etc.

Another question:  how many games actually need to run the blitter
at full speed for the _entire_ duration of the program?  It strikes
me that most that make very heavy use of the blitter don't use it
continuously:  I can't really see StarGlider II (just to pick one
at random, and yes I did see the message stating why the program
shuts down the O.S.) needing full control of the blitter when 
all you're doing is sitting in one of those tunnels trying to
decide which direction to go next.

[...]

>Joseph Chung


-- 
Dave Schreiber                        The blue leprechaun
at davids@slugmail.ucsc.edu (prefered but flakey)
or (not both) davids@ucscb.ucsc.edu   "Coffee, Darling?"