mirror of
https://github.com/PDP-10/its.git
synced 2026-01-11 23:53:12 +00:00
120 lines
4.0 KiB
Plaintext
120 lines
4.0 KiB
Plaintext
MAC-beth
|
|
|
|
Dave Lebling
|
|
June, 1971
|
|
|
|
Act IV: (A ninth floor. In the center, a PDP-10 moaning)
|
|
|
|
(Enter three losers)
|
|
|
|
1st Loser Thrice the NCP has died
|
|
2nd Loser Thrice and once the system crashed
|
|
3rd Loser Brescia cries, "'tis time, 'tis time."
|
|
|
|
1st Loser Round Tee-zero-zero go,
|
|
In the system patches go.
|
|
Crocks that in some hacker's brain
|
|
Hath drifted 'til he went insane.
|
|
Only he knows what they do
|
|
(JRST to .+1202?)
|
|
|
|
All Mumble, mumble, system crumble
|
|
DECtapes churn, directories jumble.
|
|
|
|
2nd Loser AC's and some memory take
|
|
(A working system we must fake)
|
|
Score a disk, delete some file,
|
|
Output garbage, piles and piles.
|
|
|
|
LOGIN FOO, and get a LOCK,
|
|
GUN anyone who has a block.
|
|
Then to fill this losers' brew
|
|
Generate CONVENTION II.
|
|
|
|
All Mumble, mumble, system crumble
|
|
Deflectors burn as IMLACs fumble.
|
|
|
|
3rd Loser LISTF TTY (free core none)
|
|
For IMEDIT's needed one
|
|
TECO thinks that six is fine
|
|
And for debugging, start with nine.
|
|
|
|
With 15 blocks a MIDAS deals
|
|
While over 30 MUDDLE steals.
|
|
Of course to use them takes lots more:
|
|
Then they print out NO FREE CORE.
|
|
|
|
Add to an ITS sixteen new blocks
|
|
And to them users stream in flocks
|
|
So almost all the DM group
|
|
Will lie there in a .COR loop.
|
|
|
|
All PUSHJ, PUSHJ, POPJ P,
|
|
Losers all, DM/CG.
|
|
|
|
|
|
--------
|
|
Notes:
|
|
|
|
The old project MAC Dynamic Modelling Group got its PDP-10 in 1971. It
|
|
only had 32K of memory, and the group spent a lot of time building more.
|
|
It was considered a major achievement when there was first 96K of memory
|
|
on the DM machine.
|
|
|
|
There was no memory, and no paging hardware. The system (a heavily
|
|
modified version of ITS) gave you a contiguous chunk of core, and it was
|
|
yours until you gave it back: no swapping out, but no sharing either!
|
|
People were very conscious of how much memory you used. All the
|
|
terminals (IMLAC PDS-1's and ARDSes) were in one large area, and
|
|
occasionally you would hear "I need to do a MIDAS." "Okay, I'll kill my
|
|
DDT." MIDAS needed fifteen whole pages of memory! It was considered
|
|
giant. MUDDLE needed 32, and was practically beyond the pale; true
|
|
overconsumption to use it.
|
|
|
|
In any case, there was a lot of hand-crafted hardware on the machine, and
|
|
a lot of it was really flakey. It had flakey memory, flakey memory
|
|
interfaces, a flakey network interface (the first one on an ITS), and
|
|
flakey terminals. It was literally years before the machine stayed up
|
|
for a day at a time.
|
|
|
|
DM was finally retired in late 1983.
|
|
|
|
Annotation:
|
|
|
|
Ninth floor: MAC and AI had all their machines on the ninth floor of
|
|
545 Tech Square.
|
|
|
|
Brescia: Mike Brescia, DM system wizard at the time; now with BBN.
|
|
|
|
Tee-zero-zero: T00 was the system console on DM.
|
|
|
|
LOGIN FOO: ITS has no protection, you can log in as anything you want.
|
|
It used to even automatically make you a directory when you did
|
|
so. We used to go around looking for (and flushing) directories
|
|
that were made by people logging in as a misspelling of their
|
|
real id.
|
|
|
|
LOCK: the ITS operator program, in effect. Since ITS had no protection
|
|
anyone could run it, and the GUN command logged users out.
|
|
|
|
CONVENTION II: Most of the programming on DM in those days was in
|
|
assembly language, and CONVENTION II was a coding and
|
|
documentation style manual. (Convention I was "do whatever you
|
|
feel like.") Convention II was, to say the least, unpopular.
|
|
|
|
IMLACs: the IMLAC PDS-1 was a copy of the PDP-9 with a cycle stealing
|
|
display processor added. It had a real-time editor program for
|
|
it called IMEDIT. IMLACs burned out their deflection amps a
|
|
lot. It was eventually discovered that they did this all the
|
|
time if you addressed a point off the screen. The amp would
|
|
loyally die trying to deflect the beam 90 degrees.
|
|
|
|
.COR: .COR gave you as many more blocks of memory as were contained
|
|
in its AC field. There was a program called GOBBLE at one
|
|
point which you ran by saying :GOBBLE TECO (for example). It
|
|
knew TECO was 6 blocks, so it sat around trying to get 6 blocks,
|
|
and when it did, it .VALUEd ":KILL <CRLF> :TECO <CRLF>". It
|
|
was exciting watching it print out how many blocks it had gotten.
|
|
|
|
---pdl
|