Annals of Blinkenlighten History
My search for background for my
posting from yesterday
(ok, from an hour or so ago) led me to
John Savard's wonderful paean to the front panel
of several now-antique computers.
The 360 series were IBM's premiere mainframe line throughout the 1960's.
Their model numbers were mostly multiples of 10, increasing in power
from the 360/30 and 360/40, up to the /91 and /95. Savard has some
details, next to the 360/195 front panel image:
Almost the same front panel appeared on the System/360 Model 91, which had a
pipeline but no cache, and the System/360 Model 95. The 95 was almost identical
to the 91, except that its main memory was a thin-film memory, giving it a
speed advantage; the thin-film memory had a cycle time of 120 nanoseconds; the
computers had one megabyte of this as main memory, and four megabytes of the
same regular core memory as used in the model 91, at 780 nanoseconds cycle
time, used as bulk core. [...] For comparison, for other models in the
IBM System/360 series, bulk core was provided in the form of the IBM 2361
large-capacity storage unit, with an 8 microsecond cycle time.
Only two IBM 360/95 computers were made, both for NASA. One went to the Goddard
Space Flight Center, in Greenbelt, Maryland, and the other went to the Goddard
Institute for Space Studies, part of Columbia University, in New York City.
According to IBM's 360 and Early 370 Systems by Pugh, Johnson, and Palmer, IBM
produced fourteen Model 91 computers, four of which it kept for internal use.
At least one source estimates that about 25 Model 195 computers were produced.
After that, the 360 morphed into the 370, 3090, and I think these days
their intellectual progeny live on as IBM's "Z-Series" mega-VM-mainframes.
UCLA had two of those fourteen /91's. One was at the Med Center
(aka "Health Sciences"), and the other was available for approximately
general usage to the rest of the campus users. It was run by an
organization called
"CCN", for
"Campus Computing Network" and the UCLA computer club had
a deal with CCN where each clubbie could use 18 seconds of time
per night, on CCN's 360/91. So you'd punch your programs onto
punch cards, put them in this big drawer in the club office
(3840? Boelter Hall) and then some volunteer would take the
drawers and cart them up to the machine room, run them
(or hand them over to The Operator to run), and then get
the outputs (11 by 17 fanfold paper) and bring that all
back to the club office.
My oldest brother Chris was at UCLA from 1966 or so,
and I was there from 1969 - 1973. At one point before
I was a student there (must have been 1968 or so),
Chris had a job working at Health Sciences, and I got to
write a PL/I program to do some kind of simulation of
an integration problem. Took nine whole minutes of
that 360/91's time!
I seem to recall that CCN's /91 had a whopping
sixteen MEGAbytes of CORE Memory!! Enormous!
How could anyone fill up that much space?
Anyway, this flashback ought to link to
this other flashback, which in turn links to
a related article I wrote a dozen years ago.
12:24:21 AM
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