MIT model explains how the brain can learn novel tasks while still remembering what it has already learned.
CAMBRIDGE, Mass.--They came to praise the CM5. And to bury it.
After one final chess game, Albert Vezza, former associate director of the MIT Laboratory for Computer Science (LCS), flicked the switches on the supercomputer on Wednesday evening, July 16, shutting it down after four years of memorable service.ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ The red lights flickered for the final time at 5:15pm while a VCR played the computer HAL's deathbed soliloquy from the film "2001."
"In my native Greece, we mourn at funerals, but we also drink a lot," LCS Director Michael L. Dertouzos told about 60 faculty, scientists, staff, students and guests who gathered for a good-bye party at the laboratory.
The CM5, officially a 128 processor Connection Machine Model CM5, was acquired from Thinking Machines Corporation in 1993. It was the 17th mostï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½powerful computer in the world at the time, with moreï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½power than the entire MIT Project Athena. At shutdown, it still ranked 497th.
The 6-by-3-by-6-foot CM5, the computer in the movie "Jurassic Park," was retired to make room for new equipment. Obviously, computer years are shorter than dog years.
The CM5 will beï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½placed in storage and its future is uncertain. "There was some talk of making plaques from it,"ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½said Professor Alan Edelman, "and some talk of selling it." So far, no one has made an acceptable offer.
The CM5 was the flagship of Project SCOUT, a collaborative effort that brought together architects, programmers and users from many departments and other institutions, including Boston University and Harvard, with Mr. Vezza as the principal investigator. "It captured a lot of our imagination,"ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½said Professor Dertouzos. "It was like mixing a big salad."
The mix required specialists used to working within their own discipline to coordinate and communicate with people from other fields. The excitement--and the productivity and innovation--was contagious. "It was almost like a dating service with the big machine sitting in the middle,"ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½said Dr. Thomas J. Greene, the Project SCOUT manager.
Project SCOUT produced breakthroughs in a variety of fields, including numerical algorithms for protein folding, animal and plant virus modeling, ocean modeling, modeling backflow contamination of ion thrusters ontoï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½spacecraft and planning radiosurgery of brain tumors.
The CM5 also drove MIT chess programs *Socrates and Cilkchess when they competed with great success on the computer chess circuit. Trophies from several tournaments were displayed next to the machine during the shutdown ceremonies.
During a supercomputer conference in Washington in 1994, Professor Charles Leiserson, the LCS's chess expert, offered a free *Socrates T-shirt to anyone who could last three minutes playing chess against the CM5 (computer matches usually take about five minutes). Nobody could. The time was reduced to two minutes. Still no winners. The shirts finally were distributed to anyone who competed against the CM5. Nobody wanted to schlep them back to Cambridge.
The CM5 was blessed with good fortune from the beginning. In its first chess tournament, the programmers inadvertantly introduced a bug into the timing device that should have ended the competition for the MIT team. Somehow, the programmers had simultaneously introduced a second bug, which neutralized the first one. The CM5 went on to finish third in the 1994 North American Computer Chess championships at Cape May, NJ. "That was a stroke of luck that we never fully understood," recalled Professor Leiserson.
In its final game,ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½the CM5, running the *Socrates chess program, was matched against Cilkchess, a more recent program running on a modern eight-processor Sun System computer. Fittingly, the CM5 was the winner, even though its technology was two computer generations older. "It was definitely not rigged," said Don Dailey, who wrote bothï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½programs, his grin clearly an indication that the result pleased him.
The farewell party, as much celebration as wake, was organized by Professors Leiserson and Edelman, both Thinking Machines Corp. alumni. "So many people loved this machine,"ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½said Professor Edelman, "that it didn't seem right to shut it off without a proper sendoff." That included a final message, hacked by Professor Edelman, which said: "No! Mr. Vezza, no!" The lights went out on schedule.
Before the party, Professorï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½Leiserson wrote the CM5's vital statistics on a white board in the LCS lounge area:
- 128 processors, each with 4 vector units
- "Fat Free"ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½interconnect
- 16 gigaflops peak performance
- 4 gigabytes of main memory
- 36 gigabytes of disk storage
- And nice lights!
Someone added a footnote, perhaps the appropriate inscription for the tombstone of a beloved thinking machine: "Wicked awesome."