Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!clyde.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!mintaka!wookumz.ai.mit.edu!rjc From: rjc@wookumz.ai.mit.edu (Ray Cromwell) Newsgroups: comp.sys.amiga.tech Subject: Re: Help --> How to prevent the visit from the dreaded guru Message-ID: <1991Jan7.011309.22529@mintaka.lcs.mit.edu> Date: 7 Jan 91 01:13:09 GMT References: <615@caslon.cs.arizona.edu> <134@atacama.cs.utexas.edu> Sender: daemon@mintaka.lcs.mit.edu (Lucifer Maleficius) Organization: None Lines: 26 In article limonce@pilot.njin.net (Tom Limoncelli) writes: >Every couple of months these same questions appear. Could some take >all these posts and summarize them and build a new entry for the >monthly posting? Randell? > >It could cover which Amigas have MMUs, define memory protection vs. >virtual memory vs. resource tracking, why memory protection and >resource tracking can't reasonable be added to AmigaDOS, what ^^^^^^^^^^^^^^^^^^^^^^^^^ I've been around awhile and I know these questions come up every once in awhile. The MMU issue is hard. But there is no convincing evidence to me why resource tracking and virtual memory cannot be added to the Amiga. Just look at AllocRemember(), or better yet, ArpLibrary, these are fine examples of elementary resource tracking. In fact, resource tracking is ALWAYS done, by the programmer in his own code. If a programmer didn't check for things he had aquired in his program before closing resources would be eaten up quick. All that needs to be done is move resource tracking out of the programmers hands into the system level. Granted, the programmer is still responsible for freeing things himself. Atleast(if resource tracking is implemented at the system level) buggy programs can't force a reboot, or tasks that have been suspended/killed can be unloaded from memory. Virtual memory is easier than resource tracking. Resource tracking has a memory/speed hit, but on a 68030 its well worth it.