From: norman@oclsc.org (Norman Wilson)
Subject: [TUHS] Happy birthday, Niklaus Wirth!
Date: Sun, 18 Feb 2018 15:50:46 -0500 [thread overview]
Message-ID: <1518987049.23498.for-standards-violators@oclsc.org> (raw)
As an aside about Wolfram and SMP (and one that actually has
something to do with UNIX):
I ran the VAX on which Wolfram et al (and it was very much et al)
developed SMP. It started out running UNIX/TS 1.0. I know how
that system was snuck out of Bell Labs, but if I told you I'd have
to terminate you with extreme prejudice. (I wasn't involved
anyway.)
SMP really needed dynamic paging; the TS 1.0 kernel had only
swapping. We had quite a few discussions about what to do.
Moving wholesale to 3BSD or early 4BSD (this was in 1981)
would have been a big upheaval for our entire user community.
Those systems were also notorious at the time for their delicate
stability: some people reported that they ran well, others that
they crashed frequently. Our existing system was pretty solid,
and I had already put some work into making it more so (better
handling of low-level machine errors, for example).
Somehow we ended up deciding that the least-painful path was
to lift the VM code out of 4BSD and shoehorn it into our
existing kernel, creating what we called Bastardized Paging
UNIX. I did most of the work; I was younger and more energetic
back then. Also considerably grumpier. In the heart of the
page-in (I think) code, the Berkeley guys had written a single
C function that stretched to about ten printed pages. (For those
too young to remember printers, that means about 600 lines.)
I was then and still am adamant that that's the wrong way to
write anything, but I didn't want to take the time to rewrite
it all, so (being young and grumpy) I relieved my feelings by
adding a grumpy comment at the top of the source file.
I also wrote a paper about the work, which was published in
(of all places) AUUGN. I haven't read it in years but it was
probably a bit snotty. It nevertheless ended up causing a
local UNIX-systems-software company to head-hunt me (but at
the time I had no interest in leaving Caltech), so it must
not have been too rude.
What days those were, when a single person could understand
enough of the OS to do stuff like that in only a month or two,
and get it pretty much right too. I did end up finding some
interesting race-condition bugs, probably introduced by me, but
fascinating to track down; e.g. something that went wrong only
if a page fault happened at exactly the right time with respect
to something else.
Norman Wilson
Toronto ON
next reply other threads:[~2018-02-18 20:50 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-18 20:50 Norman Wilson [this message]
2018-02-19 0:28 ` Dave Horsfall
[not found] <mailman.22.1518790085.20342.tuhs@minnie.tuhs.org>
2018-02-16 17:40 ` Paul McJones
2018-02-16 19:24 ` Bakul Shah
-- strict thread matches above, loose matches on Subject: below --
2018-02-16 13:42 Noel Chiappa
2018-02-16 21:02 ` Tim Bradshaw
[not found] <mailman.1.1518746401.1018.tuhs@minnie.tuhs.org>
2018-02-16 2:40 ` Paul McJones
2018-02-16 2:19 Noel Chiappa
2018-02-16 2:48 ` Larry McVoy
2018-02-16 4:19 ` Steve Nickolas
2018-02-16 11:27 ` Tim Bradshaw
2018-02-16 15:45 ` Nemo
2018-02-14 21:06 Dave Horsfall
2018-02-14 21:12 ` Clem Cole
2018-02-14 22:15 ` George Michaelson
2018-02-14 23:37 ` Dave Horsfall
2018-02-14 21:24 ` Toby Thain
2018-02-16 0:01 ` Dave Horsfall
2018-02-16 0:51 ` Dan Cross
2018-02-16 1:06 ` Clem cole
2018-02-16 3:10 ` Toby Thain
2018-02-16 13:36 ` Clem Cole
2018-02-16 1:18 ` Larry McVoy
2018-02-16 1:55 ` George Michaelson
2018-02-16 1:56 ` Lawrence Stewart
2018-02-16 2:38 ` Dan Cross
2018-02-16 2:41 ` Larry McVoy
2018-02-16 2:51 ` Dan Cross
2018-02-16 2:56 ` George Michaelson
2018-02-16 10:26 ` Tim Bradshaw
2018-02-16 1:25 ` Ian Zimmerman
2018-04-24 0:59 ` Ian Zimmerman
2018-04-24 3:26 ` Dave Horsfall
2018-04-24 4:31 ` Dan Stromberg
2018-04-24 13:42 ` Clem Cole
2018-02-16 2:09 ` Bakul Shah
2018-02-16 2:31 ` Toby Thain
2018-02-16 10:01 ` Tim Bradshaw
2018-02-16 12:10 ` Bakul Shah
2018-02-16 12:37 ` tfb
2018-02-16 13:34 ` Bakul Shah
2018-02-16 14:07 ` Bakul Shah
2018-02-16 20:13 ` tfb
2018-02-16 3:17 ` Dan Stromberg
2018-02-14 23:19 ` Greg 'groggy' Lehey
2018-02-14 23:31 ` Dave Horsfall
2018-02-15 17:32 ` Steffen Nurpmeso
2018-02-15 19:18 ` Ian Zimmerman
2018-02-15 20:56 ` Steffen Nurpmeso
2018-02-15 21:31 ` Jeremy C. Reed
2018-02-15 2:30 ` Nemo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1518987049.23498.for-standards-violators@oclsc.org \
--to=norman@oclsc.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).