Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!olivea!apple!keith
From: keith@Apple.COM (Keith Rollin)
Newsgroups: comp.sys.mac.programmer
Subject: Re: CompactMem with MultiFinder partitions
Keywords: Multifinder, Partitions, fragmented memory
Message-ID: <54216@apple.Apple.COM>
Date: 20 Jun 91 23:44:03 GMT
References: <1991Jun20.041856.5918@cec1.wustl.edu>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 27

In article <1991Jun20.041856.5918@cec1.wustl.edu> jyp@wucs1.wustl.edu (Jerome Yvon Plun) writes:
>If you have multiple applications being launched and terminating in random
>order, you are bound to fragment your memory and not be able to obtain a 
>application partition as big as the free memory.
>If we were dealing with handle, a call to CompactMem would do the trick
>(as in NewHandle or NewPtr).  Can a similar approach be undertaken by a
>little program that would move an entire partition in memory and update
>the value of A5 for that partition?
>
>In fact, if there exists such a tool, I would be pleased to hear about it.
>If not and the method I suggested is feasible, I might write a little
>application implementing it.

The method you suggest is not feasible. There are non-relocatable blocks
in the application heap that you cannot move. For example, window
records are non-relocatable. You can't move these when you move the app
heap without updating all references to them. And there's no way you
can find all valid references to non-relocatable blocks.

Similarly, the master pointer blocks are non-relocatable, too.

-- 
------------------------------------------------------------------------------
Keith Rollin  ---  Apple Computer, Inc. 
INTERNET: keith@apple.com
    UUCP: {decwrl, hoptoad, nsc, sun, amdahl}!apple!keith
"But where the senses fail us, reason must step in."  - Galileo