From: Clem Cole <clemc@ccc.com>
To: Larry McVoy <lm@mcvoy.com>
Cc: tuhs@tuhs.org
Subject: [TUHS] Re: DG UNIX History
Date: Sat, 12 Nov 2022 14:36:05 -0500 [thread overview]
Message-ID: <CAC20D2PM8OVgoHLf96K-u4w2Dh02ELp-6vnczTtJKGnWowEhrg@mail.gmail.com> (raw)
In-Reply-To: <20221112183623.GO652@mcvoy.com>
[-- Attachment #1: Type: text/plain, Size: 1713 bytes --]
To be honest, I've forgotten many (most) of the details. But that sounds
about right. As I remember it, it was like SunOS. The key point was that
the kernel only had one view of the memory system period, no FS
buffer cache etc...which was a departure from many of the traditional UNIX
implementations. IIRC they did not support BSD's mmap -- but check the
SVR3 docs to be sure -- they had the SVR3 user interfaces but none of the
BSD ones. They did support the System V shared memory, however. I do seem
to remember there was something funny in the driver interfaces, it was just
like UNIX only different, and that causes some heartache - but it was
fairly straightforward to move a DMA driver like getting a VME Xylogics
tape controller to work, but it took a little tweaking. I've forgotten
exactly why that was -- it's been a long time ago.
Clem
ᐧ
On Sat, Nov 12, 2022 at 1:36 PM Larry McVoy <lm@mcvoy.com> wrote:
> On Sat, Nov 12, 2022 at 01:04:30PM -0500, Clem Cole wrote:
> > On Sat, Nov 12, 2022 at 11:52 AM <arnold@skeeve.com> wrote:
> > > DG-UX was a pretty generic SVR3
> > >
> > User space was generic. But the SVR3/88K kernel was a heavy rewrite.
> > LCC did a lot of work with DG adding stuff too it -- it was very well
> done
> > by the DG team in NC. The memory and FS was well integrated.
>
> So read()/write()/mmap() all shared the same cache like SunOS? In SunOS
> the
> only things not in the page cache were directories and inodes. All data
> pages had one, and only one, place to be (ZFS broke this in Solaris,
> which has always blown my mind).
> --
> ---
> Larry McVoy Retired to fishing
> http://www.mcvoy.com/lm/boat
>
[-- Attachment #2: Type: text/html, Size: 2763 bytes --]
next prev parent reply other threads:[~2022-11-12 19:37 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-12 15:54 [TUHS] " Clem Cole
2022-11-12 16:09 ` [TUHS] " Larry McVoy
2022-11-12 16:52 ` arnold
2022-11-12 17:05 ` Larry McVoy
2022-11-12 17:09 ` Miod Vallat
2022-11-12 17:12 ` Warner Losh
2022-11-12 17:39 ` arnold
2022-11-12 17:13 ` David Barto
2022-11-12 17:37 ` Brad Spencer
2022-11-12 18:04 ` Clem Cole
2022-11-12 18:36 ` Larry McVoy
2022-11-12 19:36 ` Clem Cole [this message]
2022-11-13 1:56 ` Larry McVoy
2022-11-12 19:16 ` Dave Horsfall
2022-11-12 19:31 ` Clem Cole
2022-11-14 11:44 arnold
2022-11-14 22:11 Paul Ruizendaal
2022-11-14 22:31 ` Clem Cole
2022-11-14 23:54 ` Warner Losh
2022-11-15 6:03 ` Theodore Ts'o
2022-11-15 15:11 ` Larry McVoy
2022-11-15 15:48 ` Bakul Shah
2022-11-15 17:47 ` Warner Losh
2022-11-15 1:21 ` Stuff Received
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=CAC20D2PM8OVgoHLf96K-u4w2Dh02ELp-6vnczTtJKGnWowEhrg@mail.gmail.com \
--to=clemc@ccc.com \
--cc=lm@mcvoy.com \
--cc=tuhs@tuhs.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).