Path: utzoo!attcan!uunet!cs.utexas.edu!sun-barr!sun!imagen!atari!portal!cup.portal.com!ts
From: ts@cup.portal.com (Tim W Smith)
Newsgroups: comp.sys.mac
Subject: Re: System 7.0 Virtual Memory Question
Message-ID: <19028@cup.portal.com>
Date: 1 Jun 89 06:31:38 GMT
References: <758@cf-cm.UUCP> <653@bridge2.ESD.3Com.COM> <31723@apple.Apple.COM> <8054@batcomputer.tn.cornell.edu> <2108@internal.Apple.COM> <372@taniwha.UUCP>
Organization: The Portal System (TM)
Lines: 19

When we were developing our 68012 based VM system at Callan, the
first version just used the file system for paging.  Process nnnn
would page to/from the file /pages/nnnn.

Eventually someone got me to admit that I did it this way because I
was too lazy to write code to manage pages on the swap space.  By
that time I had a fancy memory allocation manager that was easy to
use to manage disk blocks too, and so the paging got changed to
use /dev/swap.

I kind of like paging to the file system.  It has a big advantage
in that you don't end up having to statically allocate a big
chunk of disk to handle paging.  On the other hand, the performance
is not going to be as good as going to a raw disk.

I never got around to comparing the performance of the two methods,
being distracted by Callan going under and all that.

					Tim Smith