I've got a number of DEC terminals, ranging from the VT220 to the VT520
(sadly, I got rid of my VT100 and VT102 many years ago, before I started
collecting DEC equipment instead of just using it), and some of them
have one or more burned out serial ports. Before I start taking them
apart to find out what chips were used, I figured I'd check if any of
you folks happen to know. I'd like to order a stash of replacements,
and it would be nice to have them handy before I clear the work bench to
start dismantling terminals...
Oh, and for the record: the Q-bus PDP-11/23 uses 9636ACP and 9637ACP for
output and input, respectively, while the VAX-11/630 substitutes a
9639ATC optocoupler for the 9637ACP differential receiver. (I have a
couple of spare CPU boards with damaged ports, as well, so these are all
on my shopping list already.)
Most people who graduate with CS degrees don't understand the significance
of Lisp. Lisp is the most important idea in computer science. --Alan Kay
Re: [COFF] Happy birthday, the Internet!
> From: Jim Carpenter
> But even that isn't really correct, as the Internet is a network of
> networks and Arpanet was all alone.
Correct: the ARPANET was merely an ancestor (albeit an important one) of the
Internet. (The most important, in terms of technical influence, was CYCLADES,
"the key intermediate technical step between the ARPANET and the Internet".)
The ARPANET was later sort of subsumed into the Internet, as its original
long-haul backbone ("sort of" because the ARPANET's main protocol was
discarded, in doing so), but that's not too important.
If you want to select _a_ birthday for the Internet, I'd pick the day they
settled on the IPv4 packet format; we know when that was, it was the second
day of the 15/16 June, 1978 meeting (see IEN-68). I'm not wedded to that
date, if someone has a better suugestion (e.g. the firt PRNET to ARPNET test),
I'm open to hearing why the alternative's preferable.
Born on this day in 1969 with the publication of RFC-1 "Host Software" by
Steve Crocker, it basically specified the ARPAnet and the IMPs.
Oh, and it really peeves me when the stupid media call it "the internet";
it's a proper noun, hence is capitalised.
On Fri, Apr 2, 2021 at 1:50 PM Theodore Ts'o <tytso(a)mit.edu> wrote:
> Out of curiousity, how was TCF different or similar to Mosix?
Many similar ideas. TCF was basically the commercial implementation of the
Locus, which Jerry and students built at UCLA (one 11/70s original). I
want to say the Locus papers are in some early SOSPs.
MOSIX was its own Unix-like OS, as was Locus [and some of this was in
Sprite too BTW]. TCF was a huge number of rewrites to BSD and was UNIX.
The local/remote restructuring was ad-hoc. By the time Roman and I lead
TNF, we had created a formal VPROC layer as an analog to the VFS layer
(more in a minute). TNC was to be the gut of Intel's Paragon using OSF/1
as base OS.
The basic idea of all of them is that the cluster is looks like a single
protection domain with nodes contributing resources. A Larry says a ps is
cluster-wide. TCF had the idea of features that each node provides (ISA,
floating-point unit, AP, *etc*..) so if a process needed specific
resources, it would only run on a node that had those resources. But it
also meant that processes could be migrated from a node that had the same
One of the coolest demos I ever saw was we took a new unconfigured PS/2 at
a trade show and connected the ethernet to it on the trade show network,
and put in a boot floppy. We dialed back into a system at an LCC, and
filled in some security things, details like the IP address of the new
system and soon it booted and joined the cluster. It immediately started
to add services to the cluster, we walked away, and (overnight) the system
had set up the hard disk and started caching locally things that were
needed for speed. Later I was editing a file and from another screen
migrated the process around the cluster while the editing was active.
The problem with VPROC (like VFS) is it takes surgery all over the kernel.
In fact, for Linux 2.x kernel the OpenSSI
<https://sourceforge.net/projects/ssic-linux/> folks did all the kernel
work to virtualize the concept of process, which sadly never got picked up
as the kernel.org folks did not like it (a real shame IMO). BTW, one of
the neat side effects of a layer like VPROC is things like
checkpoint/restart are free -- you are just migrating a process to the
storage instead of an active processor.
Anyway, Mosix has a lot of the same types of ideas. I have much less
experience with it directly.
On Fri, Apr 02, 2021 at 09:11:47AM -0700, Larry McVoy wrote:
> > Long before Linus released Linux into the wild in 1990 for the >>386<< much
> > less any other ISA, IBM had been shipping as a product AIX/370 (and AIX/PS2
> > for the 386); which we developed at Locus for them. The user-space was
> > mostly System V, the kernel was based on BSD (4.1 originally) pluis a great
> > deal of customization, including of course the Locus OS work, which IBM
> > called TCF - the transparent computing facility. It was very cool you
> > could cluster 370s and PS/2 and from >>any<< node run a program of either
> > ISA. It has been well discussed in this forum, previously.
> It's really a shame that TCF didn't get more widespread usage/traction.
> That's exactly what BitMover wanted to do, I wanted to scale small cheap
> SMPs in a cluster with a TCF layer on it. I gave some talks about it,
> it obviously went nowhere but might have if we had TCF as a starting
> point. TCF was cool.
(Moving this to COFF...)
Out of curiousity, how was TCF different or similar to Mosix?