Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!udel!mmdf
From: mcvax!melkart!tih@uunet.uu.net
Newsgroups: comp.os.minix
Subject: Moving memory around.
Message-ID: <7493@louie.udel.EDU>
Date: 28 Jan 89 17:20:14 GMT
Sender: mmdf@udel.EDU
Lines: 23

Before I start trying to implement the code:  I'd like to change the memory
manager a little, so that when a fork or exec asks for memory, and there isn't
a large enough hole available, MM will attempt to make such a hole by closing
up existing blocks.  This would be accomplished by moving blocks of allocated
memory, and updating the segment registers in process data structures.  Now,
will this cause problems elsewhere?  Might, for instance, other kernel programs
have segment information in local variables at the time, which would become
invalidated by such moves?

This would, of course, be a preliminary to implementing swapping -- if we can
move memory around like this, there's nothing to keep us from moving it onto
a swap partition on disk (RAM disk, if available) and moving it back into RAM
before scheduling the process to be run.

-tih

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Tom Ivar Helbekkmo                                ..!mcvax!ndosl!melkart!tih
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