The story so far: It's 1965 and I'm at the Courant Institute (NYU) Computer Center.

So that's where I found myself forty years ago, at the age of 21 with my first real job as a programmer. Eventually, my assignment was to keep the FORTRAN compiler and libraries, assembler, and associated "products" up and running. Others maintained the operating system. Back then CDC was having a lot of trouble releasing its much touted SIPROS operating system. But Serial #4 6600 was already installed and powered up at the Institute's new building on Mercer Street in the Village. CDC engineers were running an operating system called COS (Chippewa OS, because the 6600 was designed and built at Seymour Cray's own lab in Chippewa Falls, Wisconsin.) COS was intended just as a test system for site engineers. There was very little documentation (a single spiral bound xeroxed collection of strange notes and diagrams -- I still have one). At one point, Max Goldstein, the Center's director, gave up waiting for SIPROS and asked the systems group (me and three others) to get COS running as a production system. Trial by fire!

It was a bare-bones OS. For example, we had two high-speed line printers (those form-fed 136 column monsters), but the OS only could handle one printer at a time. My first job was to learn enough assembler to rewrite the printer driver to handle two print streams and two printers. (Parallel programming!) We had an early version of a two-printer driver, but it didn't really work very well ... it put alternate print lines on alternate printers! But somehow I did manage to pull it off and within a few weeks we had both printers running.

What I do remember the most about that period was system time!

If you lived thru the period of large computer mainframe system installations like the 6600, you will remember system time. That was when the computer would be unloaded of all jobs and turned over to the systems group to test new versions of the OS without doing damage to the job stream.

It was usually at 2am. For a number of days I got the whole machine room for myself to test out new versions of the print driver. And I'd be in there all alone. The OS was written in assembly language for the 12-bit 6600 peripheral processor (PP) and then key-punched into cards and compiled into a binary program, which was then punched onto cards. The 6600 had a 60-bit CPU and 10 of these PPUs. All the lower I/O operations, like reading the disk and functioning the printer, were done by PPU programs.

Eventually I was able to get both printers printing complete separate output jobs. But the next operator wasn't going to arrive until 6am. And I was the only person there. So if I finished at 3 there was nothing else to do but turn the whole system off and go home! Now, turning off a $14 Million computer system is not something you take lightly. The CDC engineers had printed up a set of instructions on how to go around the room turning peripherals off in the proper sequence. And then, how to turn off the main unit. I remember pausing at the switch, heart pounding, going thru in my mind all the steps and checking them off... was everything ready? And then opening the safety release and pushing the switch.

What would happen next was really scary. You suddenly realized how much background noise there was, and how you had learned to ignore it. Because soon all the fans and pumps (water cooled) would start shutting off, and then you could hear the massive disks (eight 5' diameter platters arranged in a cabinet mounted vertically) would start spinning down with an high loud whirrr slowly lowering in pitch. It took many minutes for the disk to completely spin down. And then, this room that was so full of sound was now ... deathly ... quiet. My neck would be in a cold sweat. I'd gather up my stuff, click off the lights, and get the hell out of there as fast as I could.

That was system time.