Subject: Re: pmax for development?
To: Rich McClellan <richmc@entropy.ucsc.edu>
From: Chris Jones <cjones@honors.montana.edu>
List: port-pmax
Date: 03/10/1998 10:25:19
On Mon, 9 Mar 1998, Rich McClellan wrote:

> I have three DECstation 5000/240s here running Ultrix 4.2.  I am
> interested in running NetBSD.  Is NetBSD on the DECstation ready as a
> development environment?  I've looked through www.netbsd.org, but I am
> having a difficult time getting an idea of the stability/functionality of
> the OS.

I've got a DS5000/240 that I just (last week) converted to NetBSD.  It
rarely has fewer than a dozen mathematicians on it, running everything
from pine to Matlab.  I've had the following problems:

1. NetBSD, unlike Ultrix, does not have support for memory error
correction.  Consequently, you'll want to check uerf for memory errors
before switching over to NetBSD; otherwise, you could end up with random
kernel panics and core dumps.  (I've seen the latter.)

2. Emacs can not yet undump itself under NetBSD.  The best solution I've
found is to compile emacs under Ultrix, install it, and tar the whole
thing up.  Then you can untar this under NetBSD and run it under binary
emulation.  Works just fine.

3. Several commercial programs that I've dealt with do things like running
uname, and parsing its output.  Of course, they don't find the string
'Ultrix' in there anywhere, so they tend to bomb out for lack of knowing
what hardware they're running on.  This can almost always be fixed by
appropriate hackery.

4. There's the obvious problem with lack of console driver support for
anything except PMAG-A and PMAG-B.  Hopefully, there will be PMAG-C and
PMAG-D Xserver support soon, if Jonathan ever sends me the appropriate
API.  (Hello!)

5. I'm not sure exactly what caused it, but on my machine, I was hitting
panics in vm_fork.  (This may be because the machine is heavily used, and
has lots of processes.  Not sure there, though.)  I doubled the size of
the PTE map, and they went away.  This problem is another one that should
probably be fixed soon, if I understand correctly.

The pkgsrc distribution is a *huge* help in converting over from one OS to
another, BTW.  Many of the programs that were in highest demand (or even
mission-critical) were in the pkgsrc distribution.

All in all, I'd say that NetBSD was definitely the way to go for our
department.  With Ultrix licenses permanently expiring on August 1, we
wanted to begin making the conversion now, so we'd have plenty of time to
iron out any potential bugs.  The conversion of several apps took some
hacking, but nothing as bad as I've had to do for other apps I've
installed under e.g. Solaris.

Chris

-------------------------------------------------------------------------------
Chris Jones                                      cjones@rupert.oscs.montana.edu
           Mad scientist in training...
"Is this going to be a stand-up programming session, sir, or another bug hunt?"