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From: miguel@eng.umd.edu (Frank San Miguel)
Newsgroups: comp.sys.amiga
Subject: A3000: What about MEMORY MANAGEMENT ???!
Keywords: GURU, crash, Software Error
Message-ID: <1990Jun4.223441.22565@eng.umd.edu>
Date: 4 Jun 90 22:34:41 GMT
Sender: news@eng.umd.edu (The News System)
Distribution: usa
Organization: College of Engineering, Maryversity of Uniland, College Park
Lines: 27

I've been reading the c.s.a since A3000 was announced and I still haven't
heard an adequate description of memory management on the A3000.  There
was some mention of _ENFORCER_ option, but I don't know what this is.

Question:

  The 68030 has a nifty MMU which supports multiple levels of
  mappings.  It seems like it wouldn't be a big deal to provide
  memory protection using the MMU - not real virtual memory, just
  some protection so GURU is less heard from.  The memory allocation 
  routines would have to be changed, but the mapping would be done
  transparently.
 
  When I asked my local dealer this question, he said memory protection
  is on its way in future revs of the OS, but that "memory protection
  is VERY hard to do."  I don't get it - there are alot of tricky things
  about operating systems, but it seems that memory protection deserves
  a fair amount of attention from system designers, especially in a
  multitasking machine like the Amiga!!!

  Since I haven't done any low level programming on the Amiga, I assume
  I've missed something.  Are there are problems with chip ram, addressing
  of the custom chips, or compatibility problems.  Can anyone (Commodore 
  included) shed some light on this subject?


			- Frank San Miguel