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From: Dennis Lee Bieber <wlfraed@ix.netcom.com>
Subject: Re: "High water" Memory fragmentation still a thing?
Date: Sat, 04 Oct 2014 16:20:44 -0400
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On Sat, 04 Oct 2014 11:02:02 +1000, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> declaimed the following:

>
>Way back in the mid 1980s, Apple Macintoshes used a memory manager which
>could move memory around. Given that the Macs of the day had 128K of RAM,
>of which something like a third or a half was used for the screen, being
>able to move blocks of memory around to avoid fragmentation was critical,
>so I guess that proves that it would help at least one thing.
>
	It also relied upon everything being double-dereferenced... Allocating
memory did not return the address of the allocated memory, but a handle
(pointer) to a structure that itself held the address of the target memory.

	Handles could not be moved, but the memory compaction algorithm was
free to move the allocated memory and update the handle to point to the new
location. Of course, this means one better not run out of space in the
"handle table" <G>

-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/