[688] in netbsd-help mailing list archive
Re: Linux/NetBSD (w/AFS?) on memory-constrained machine
daemon@ATHENA.MIT.EDU (Erik Nygren)
Thu Feb 1 02:29:35 1996
To: Danilo Almeida <dalmeida@MIT.EDU>
Cc: linux-help@MIT.EDU, netbsd-help@MIT.EDU
In-Reply-To: Your message of "Thu, 01 Feb 1996 01:40:30 EST."
<199602010640.BAA00390@playdoh.mit.edu>
Date: Thu, 01 Feb 1996 02:25:36 -0500
From: Erik Nygren <nygren@MIT.EDU>
> There's a 386/25 with 5Mb RAM in my living group currently running a
> pre-1.0 version of Linux. We'd like to have it be more usable,
> possibly running AFS if memory permits (fat chance). First, I would
> ...
I haven't used NetBSD, so it may do better or worse. I'll let others
speak to that.
Linux can normally deal ok with 5MB of RAM as long as you don't try to
run AFS or X. I know that with 4MB of RAM, the machine will swap to
death and will fail to start AFS. On a 5MB system, it might be
possible if you stripped all the devices you didn't need out of the
kernel and started up afsd with the right options. Doing so would
probably leave you with about 1MB of memory for user space processes
which might be enough for Athena login and a shell and maybe mh. You
probably would get pretty lousy performance if you tried to run emacs
or anything else like it while AFS was running.
Apparently, one person has a set of patches to make a very stripped
down kernel that will allow Linux to run on a machine with 1 or 2MB of
RAM. They probably take enough out that AFS probably wouldn't load or
work.
I'd suggest at least trying to build a small Linux 1.2.13 kernel and
then modifying rc.afs to work in a low memory situation and then
trying to otherwise pare down the machine. For example, don't start
zhm unless you need to, modify /etc/inittab to reduce the number of
getty's running, use a name server rather than running named (don't do
this unless you really need to, which you do in your case because
named takes around 200k). Also make sure that you have all elf or
all a.out libraries. Mixing them means that you need memory for
both. If all else fails, 5MB is more than enough to run comfortably
without X or AFS and should allow people to log in and zephyr or
telnet out to dialup machines for reading mail.
Erik
