Trying NetBSD 9.1 on KA650 and VAXstation 3100m38

[Boris Gjenero <boris.gjenero%gmail.com@localhost>]

My fastest VAXen are my VAXstation 3100 m38 with 8 MB RAM and a KA650 
based system in a BA123 with 16 MB RAM. I wanted to see what happens if 
I boot the latest NetBSD release, thinking about maybe doing some work 
on it and making some contributions.

Trying to netboot 9.1 on the VAXstation 3100 m38, I get an immediate 
crash when boot from 9.1 starts running, with no output from boot. The 
firmware restarts from the beginning with "A42-B  V1.3", all the tests, 
and then "?21 CORRPTN". Older 8.x boots cause the same problem. Boot 
from NetBSD 7.2 works and can netboot the 9.1 kernel. The GENERIC kernel 
reports:
total memory = 8072 KB
avail memory = 3492 KB
That's not terrible for a GENERIC kernel, but I didn't even attempt a 
multi-user boot. In single user mode, even "cat /dev/null" is slow.

The KA650 CPU is a bit slower, but the 16 MB of RAM should help. Boot 
from NetBSD 7.2 seemed to hang after the initial banner, but boot from 
9.1 worked and could netboot NetBSD 9.1. The memory situation is better:
total memory = 16328 KB
avail memory = 11500 KB
I did a multi-user boot, which took over 10 minutes with some stuff 
disabled, starting only cron, inetd and syslogd. Memory does not seem to 
be a huge problem here, and the KA650 is faster in multi-user than the 
VS3100m38 in single user. I could even initiate outgoing ssh without it 
being ridiculously slow. Surprisingly, changing a password or logging in 
locally with a password was slow, probably because the hashing algorithm 
has been upgraded to better resist password cracking.

So, you could say the KA650 system is usable, but it's so slow that it's 
not fun to use anymore. I don't suppose compiling a stripped down custom 
kernel could help much here. That would probably only free up some 
memory, and other factors are also making NetBSD 9.1 slow on this old 
hardware.

In the past, I was using NetBSD 1.3_BETA, which seems much faster. 
That's where I got QDSS working in March 1998. I was quite excited about 
it: https://mail-index.netbsd.org/port-vax/1998/03/01/0011.html . I 
don't think I would similarly enjoy doing stuff with a much slower 9.1. 
It seems my VAXen are only useful for running historical operating 
systems now. I'm a little bit sad but not complaining. With these 
results NetBSD has done better than some other operating systems.

Boris