Wednesday, August 27, 2008

Another anniversary: lessons learned from a 1991 mainframe elevation on this date


I do like my own personal anniversaries, don’t I. Today is August 27. On this day in 1991, although it was a Tuesday, I made an elevation at work that would live, not in infamy, but would at least set the tone for work life for some time to come. There’s a moral tone, and a lesson for a new generation of IT people, perhaps.

We had a salary deduction billing system written in COBOL and IDMS (with VSAM transparency), that printed out separate bills to mail to employer-clients. The project was to stack the bills and make them easier to mail, eliminating the need for one or two clerical positions in the user era. (Yes, even before the days of kiddie entrepreneurs in dorm rooms, IT professionals were in the business of eliminating jobs, while creating new ones). We actually ran only three more bills that day after the elevation (we called them “moves”) but the next day, it took ten hours to get through about 100 bills. (We called them “The Bills” which became more controversial than the much more complicated but corresponding collections system.) With technology available then, the contention with multiple jobs going against the VSAM file (despite SHARE options and configuration) was crippling. Once in a while one would crash because of the contention. The transparency did not work perfectly.

In time it got better, and two years later no one thought anything about it. The processor improved (we had IBM MVS emulated on a Hitachi machine), operating system changes improved VSAM and even disk access. By the end of the 1990s, and after a move to Minneapolis, the same mix of jobs could start around 5 in the morning and finish easily in less than an hour. No one gave it a thought. The system faded into corporate obscurity.

What I understand is that same experience occurred for programmers who learned the Vantage administrative systems for life insurance. In the early 1990s, the cycles took forever to process even 50000 policies. There was a competitor, VLN (with a similar technical approach), from San Antonio, whose software vendor went out of business. Vantage processing greatly improved in the mid 1990s, and Vantage would rule the world. Now it is a sought-after skill in an otherwise sporadic mainframe job market.

There was another part of the story. In the early 1990s, we had gotten CA-Librarian, and were not always careful to enforce a rule that a source element had to be manually locked ("processed") before it was elevated. "Data control" did try. (I remember some screenplay-like dialogue: "Moves!" "Rejects!"). If that rule was not followed, source-load-module integrity could be compromised. Later, automated procedures (was with Harvest, Changeman and Endeavor) would enforce that rule.

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