13 Nov
2022
13 Nov
'22
1:36 a.m.
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(a)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(a)skeeve.com> wrote:
done
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 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