Two Linux clusters among Top 10 fastest computers

Two federally owned Linux clusters now rank among the 10 fastest systems in the world.

Five of the planet's top 10 supercomputers, listed in a semiannual ranking of big systems, are owned by the U.S. government, and two others reside at research centers that receive substantial federal support.

The coveted top spot, however, still goes to a Japanese system called the Earth Simulator, which has a benchmark speed of nearly five times the fastest American computer.

A team of computer scientists from the United States and Germany released the new Top 500 list today in preparation for next week's SC2002 High-Performance Networking and Computing conference in Baltimore.

Making their debut in the top 10 are Linux clusters at Lawrence Livermore National Laboratory in Livermore, Calif., and the National Oceanic and Atmospheric Administration's Forecast Systems Laboratory in Boulder, Colo.

The fifth-ranked Livermore cluster contains 2,304 2.4-GHz Intel Pentium Xeon processors, which together have a theoretical peak speed of 11 trillion floating-point operations per second. Built by Linux Networx Inc. of Sandy, Utah, the clustered system scored 5.69 TFLOPS on a linear-algebra benchmark traditionally used to measure supercomputer performance.

NOAA's Linux cluster, developed by High Performance Technologies Inc. of Norfolk, Va., sports 1,536 2.2-GHz Xeon chips and registered more than 3.3 TFLOPS on the benchmark.

NOAA uses the Linux system for weather and climate research, whereas its so-called operational (daily) weather forecasts are generated at the agency's National Centers for Environmental Prediction in Maryland. In a measure of how fast the supercomputing industry is changing, NCEP's two IBM p690 supercomputers, ranked among the top 15 one year ago, now sit at 24th and 25th place.

The two fastest U.S. computers are twin sections of the Hewlett-Packard Q system at the Energy Department's Los Alamos National Laboratory. Each section generated more than 7.7 TFLOPS on the standard benchmark. Q, part of the Accelerated Strategic Computing Initiative, was built to simulate the aging of nuclear weapons.

The IBM-built ASCI White system at Livermore sits in fourth place at 7.2 TFLOPS, and another IBM system, a 3.2-TFLOPS computer at the National Center for Atmospheric Research in Boulder, is ranked 10th fastest. At 4.46 TFLOPS, a Hewlett-Packard (formerly Compaq Computer Corp.) AlphaServer SC system at the Pittsburgh Supercomputing Center ranks sixth.

The Intel-based ASCI Red system at Sandia National Laboratories, which held the title of world's fastest computer from 1997 to 2000, now ranks only 15th on the semiannual list.

The U.S. government owns 90 of the 500 computers on the new list.