P. David Lebling's MAC-beth poem.

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doc/pdl/mac.beth

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+	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