Newsgroups: comp.os.minix
Subject: Re: Minix run on an old 128K or 512K Mac?
References: <7cf4cc$fj6$1@infoserver.bgsu.edu>
Organization: Rochester Institute of Technology, Rochester, NY
From: aje9383@osfmail.isc.rit.edu (Andrew Erickson)
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In article <7cf4cc$fj6$1@infoserver.bgsu.edu>,
Zachary H. Burns <zburns@opie.bgsu.edu> wrote:
>Does anyone know if Minix will run on the 128K or "Fat Mac"?
>

128K mac:  no--not without a third-party memory expansion, at least. 

512K mac:  it would be *very* tight for memory.  One might be able to log in
to such a system, if one had virtually no disk cache and set the heap to
some obscenely small thing.  I doubt one could recompile the kernel.

Additionally, a hard drive is a very helpful thing to have; an 800K
filesystem is barely large enough for doing straightforward things.

Here's a quick and rough breakdown of how my system (4MB Mac SE, MacOS 7.0)
uses memory when running MacMinix:

MacOS stuff:  about 950KB or so (although this varies a bit)
   (Finder, system, a couple of little inits.)

Minix:  about 3000K, divided into:
Heap:  400K or so (probably could be less)--this is where the user interface
bits live for the MacBoot application--things like print drivers, window
pointers, dialog box resources, and the like.
Ram disk:  0K
Disk Cache:  320K  (I figure a big disk cache is a better performance
enahncer than a smallish disk cache and a ramdisk.)
Rest of kernel:  300K
Free to user:  2000K

All figures are approximate.  Under system 6, on a 512 K machine, MacBoot
could get perhaps 400-450K of memory; it would be hard to get a big enough
heap, a small kernel/fs, and a user process in.

1 MB or more memory with a hard drive would be the minimum system I would
recommend for being able to do anything reasonable (e.g. recompile the
kernel, etc.)  As distributed, at least the ftp-version, you absolutely need
a hard drive or equivalent mass-storage device with about 10MB free.

HTH,
--Andrew Erickson, aje9383@cs.rit.edu
