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From: philip@Kermit.Stanford.EDU (Philip Machanick)
Newsgroups: comp.sys.mac.system
Subject: Re: Memory (de)fragmentation
Message-ID: <1990Jun1.053103.8277@Neon.Stanford.EDU>
Date: 1 Jun 90 05:31:03 GMT
Article-I.D.: Neon.1990Jun1.053103.8277
References: <4372@castle.ed.ac.uk> <16797@phoenix.Princeton.EDU> <JUH.90May28095602@hutcs.hut.fi> <JUH.90May29144638@hutcs.hut.fi> <1990May29.145842.18701@kth.se> <JUH.90May30163659@hutcs.hut.fi>
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Organization: Computer Science Department, Stanford University
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In article <4372@castle.ed.ac.uk>, nick@lfcs.ed.ac.uk (Nick Rothwell) writes:

> Virtual memory solves these problems, of course, since then the
> fragmentation of the application's memory is virtual (sic), and
> shouldn't cause physical fragmentation; things can be moved in
> physical memory (or to/from disk) without the virtual addresses
> changing.
> 
> This implies that VM makes the whole handles business obsolete (yes?)

No it doesn't (sigh). Apple is still using 1 address space for everything
(I've been told - I don't have a copy of System 7). This means there will
_still_ be fragmentation even with VM, but you'll be able to hide it better
by allocating a large virtual address space.

Philip Machanick
philip@pescadero.stanford.edu