Xref: news2.mv.net comp.os.msdos.djgpp:852
From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: malloc/free ends up fragmenting dynamic memory?
Date: Tue, 06 Feb 1996 07:49:04 -0800
Organization: &tSftDotIotE
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Message-ID: <31177870.7944FD77@alcyone.com>
References: <4f5sm8$2kt AT cardinal1 DOT Stanford DOT EDU>
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

John Beale wrote:

> I am guessing that the many malloc/free operations fragments the memory
> store analgous to hard disk filesystem fragmentation with many saves and
> deletes, such that a contiguous memory segment for a large malloc() can no
> longer be found. Is there a malloc_unfragment() command or equivalent?  How
> do other people handle this problem?

With pointer-based allocation, there's no way to defragment memory, since you
can't move a block of memory _and_ update the pointers which happen to be
pointing to (and in) it.

On the Macintosh, a whole new level of abstraction is introduced to deal with
this problem -- the handle (which is a pointer to a pointer).

The solution to this is to either 1. get more memory (not all that unreasonable
of a request these days) or 2. devise a way to not fragment memory in the first
place (this depends entirely on your application).

-- 
Erik Max Francis, &tSftDotIotE. && max AT alcyone DOT darkside DOT com || max AT alcyone DOT com
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