Path: utzoo!utgpu!watserv1!ria!uwovax!7103_2622
From: 7103_2622@uwovax.uwo.ca (Eric Smith)
Newsgroups: comp.sys.atari.st.tech
Subject: floppies as swap space
Message-ID: <6916.26ec1e71@uwovax.uwo.ca>
Date: 11 Sep 90 03:14:57 GMT
References: <1990Jul31.165603.20869@msuinfo.cl.msu.edu> <1407@wet.UUCP> <1990Sep10.105324.26957@agate.berkeley.edu>
Lines: 29

In article <1407@wet.UUCP> nut@wet.UUCP (adam tilghman) writes:
>In article <1990Jul31.165603.20869@msuinfo.cl.msu.edu> schultzd@kira.uucp (David Schultz) writes:
>>
>>2.)  Is there any program that allows you to use a floppy drive as
>>swap space to get more memory in an ST.  I realize this would be
>>painfully slow, but until I can afford more mem, it would have to do.
>>It would be infinitely more helpful on a nig hard drive.  (Set aside
>>an x meg partition on the hard drive and treat it as internal memory.
>>Virtual mem on the ST!!!)
>
>  If you are using just a plain-vanilla 68000 in your machine, this is
>completely impossible.

Anything's possible :-). It's true that the 68000 doesn't support demand
paged virtual memory. (If you really must have it, you can always write an
interpreter for a virtual machine; but this will be *slow*). However,
swapping whole processes in and out of memory is possible, if the processes
don't intercept any interrupt vectors and don't mess with memory they don't
own. I plan on adding this feature to MiNT at some time (unless some
intrepid programmer beats me to it -- the hooks are already there in the code).
Done properly, swapping need not even be very slow; typically you'll only
have one process running, with others sitting in Pexec() waiting for children
to finish -- prime candidates for swapping.
--
Eric R. Smith                     email:
Dept. of Mathematics            ersmith@uwovax.uwo.ca
University of Western Ontario   ersmith@uwovax.bitnet
London, Ont. Canada N6A 5B7
ph: (519) 661-3638