Portland, Ore. NEC could be bidding to reclaim its place as maker of the world's fastest supercomputer when unofficial rankings are announced this week. But IBM, which toppled NEC from that perch a year ago, plans to defend its crown and last week added a world-class contender to the field.
Indeed, until the latest challenge from NEC, it appeared likely that IBM would take three of the top five positions in the new ranking of supercomputers and that another U.S. company, Silicon Graphics, would nail down a fourth.
The list is to be released at the 20th International Supercomputer Conference, which begins tomorrow in Heidelberg, Germany.
IBM Corp. (Armonk, N.Y.) expected to snag the top two slots. Silicon Graphics Inc. (Mountain View, Calif.) and Tokyo-based NEC Corp. were expected to vie for third and fourth, with IBM also taking the fifth spot. Prestigious supercomputing systems are seen as a measure of scientific and national competitiveness.
In the early betting, IBM's BlueGene/L supercomputer was the odds-on favorite to retain the top slot with 91.8-teraflops peak performance. The BlueGene/L uses 32,768 PowerPC440 central processing units and is being upgraded to 130,000 CPUs, to yield a projected performance of 360 Tflops. The BlueGene/L is installed at the U.S. Department of Energy's Lawrence Livermore National Laboratory (Livermore, Calif.).
Moving into second place was an IBM supercomputer dubbed BlueGene/W, recently installed at IBM's Thomas J. Watson Research Center in Yorktown Heights, N.Y., and billed last week as the world's most powerful privately owned supercomputer. The BlueGene/W tops 91.29 Tflops using more than 30,000 PowerPC CPUs.
Third place was expected to go to Silicon Graphics' Altix system, housing 10,160 Voltaire Infiniband 1.5-GHz CPUs and topping 60.9 Tflops. The system is installed at the National Aeronautics and Space Administration's Ames Research Center in Mountain View, Calif.
Fourth place was expected to go to NEC's Earth Simulator, which uses 5,120 CPUs to top 40.9 Tflops in its SX-6 spin. But an updated model, the SX-8, is said to have three times the horsepower of its predecessor and could, if it lives up to its billing, mean all bets are off in the supercomputer standings.
If the NEC challenge does not materialize, IBM's Barcelona Supercomputer Center in Spain is expected to nail down fifth place. It has 3,564 PowerPC970 CPUs running at 2.2 GHz, which enables it to best 31.4 Tflops.
The fastest supercomputer list will be released by the "Top500" organization (http://top500.org), which independently assesses supercomputer performance.
Its latest list was released last November. Top500 measures supercomputer performance using the "Linpack" benchmark. Linpack was created by University of Tennessee computer science professor Jack Dongarra to compare computers that are solving a dense system of linear equations.
The Top500 version permits the supercomputer owner to scale the size of the problem and to optimize it to achieve both a best peak and sustained performance metric. While not reflecting the overall performance of a supercomputer, Linpack is widely accepted as a measure of peak performance of large multiprocessor computer systems.