Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!swrinde!ucsd!ogicse!blake!Tomobiki-Cho!mrc
From: mrc@Tomobiki-Cho.CAC.Washington.EDU (Mark Crispin)
Newsgroups: comp.arch
Subject: Re: Multics & Memory mapped files
Message-ID: <5737@blake.acs.washington.edu>
Date: 13 Feb 90 20:17:59 GMT
References: <5180@crdgw1.crd.ge.com> <12780026@acf4.NYU.EDU> <6662@internal.Apple.COM>
Sender: news@blake.acs.washington.edu
Organization: Mendou Zaibatsu, Tomobiki-Cho, Butsumetsu-Shi
Lines: 21

In article <6662@internal.Apple.COM> desnoyer@apple.com (Peter Desnoyers) writes:
>If I remember correctly from my computer architecture class several years 
>back, there is a substantial penalty in kernel complexity to implement a 
>paging scheme which can page from arbitrary files instead of a 
>pre-allocated contiguous chunk of disk.

Is this true in all cases?  Suppose the only difference between the
"swap space" and the "file space" is that the file space has a
directory and naming structure associated with it.  The swap pointers
are the same in both cases (disk addresses), so the only difference is
in how the swap pointer was set up.

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