Category: WarStories

Q/A Testing

   While working on a software package to move Odd Lot orders/reports between brokers and the Odd Lot dealer, we were doing our usual Q/A, including [what we thought were] every possible bad input from brokers and Odd Lot dealer.

   Aside from the usual OS-MVT consoles, the system was controlled by operators manning 83B3 teletypes. One of these operators said she could crash the system any time. When challenged, she planted her elbow firmly on the keyboard of an 83B3, sending utter garbage into the system. She did indeed crash the system and we realized that garbage input could come from unexpected places.

Working Hard To Be Lazy

   From about 1974 until the late 1980s, I was responsible for maintaining Market Data System II, the mainframe system which gathered and reported trades on the New York Stock Exchange. This system was based on OS MVT Release 11 and was heavily customized/modified by IBM, with the promise to support it forever. In addition to a modified OS, IBM coded components to handle non-standard hardware and memory, as well as the infrastucture to support ‘applications’ modules.
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How I Saved The West

In 1987, the NYSE had several computer systems in operation. The oldest and most critical one was the Market Data System known as MDS-II. This system gathered trading information from the Trading Floor and drove the traditional ticker tape as well as distributing the trade data over higher speed synchronous lines. Of the various systems, MDS-II was the only one which was absolutely critical to trading. While failure of the other systems was an inconvenience, failure of MDS-II halted trading completely, resulting in a lot of lost revenue for NYSE and its member firms.
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