IBM’s Roadrunner maintained the number one spot in the latest edition of TOP500 Supercomputers, but that spot was closely monitored by the Cray XT5, dubbed Jaguar, the second to break the petaflop/s (one quadrillion floating point operations per second) barrier.

Roadrunner, the supercomputer at Los Alamos National Laboratory, has a top performance of 1.105 petaflop/s, while the Jaguar supercomputer, at the Oak Ridge National Laboratory, posted a top performance of 1.059 petaflop/s. Both systems are operated by the U.S. Department of Energy.

Pleiades (the new SGI Altix ICE system installed at NASA Ames in Moddett Field, Calif.) came as the number three supercomputer, followed by the IBM BlueGene/L system at the Department of Energy’s Lawrence Livermore National Laboratory, and the IBM BlueGene/P system installed at the Department of Energy’s Argonne National Laboratory. All of them have achieved under 500 teraflop/s performances.

On international level, nine of the top 10 supercomputers of the world are located in the United States, seven of which are operated by the Department of Energy. The most powerful system outside the United States, and the largest to be operated with Windows HPC 2008 operating system, is the Chinese Dawning 5000A at the Shanghai Supercomputer Center, the latest edition of the TOP500 revealed.

The TOP500 also revealed that 75.8 percent of the systems listed use Intel processors, a popularity that has remained constant for the past six months. IBM Power and AMD Opteron processors come second, with 12 percent and 11.8 percent respectively.
Furthermore, 336 of the top 500 supercomputers use quad-core processor based systems, while 153 of them use dual-core processors. Only 4 systems still use single core processors, while 7 systems already use IBM’s advanced Sony PlayStation 3 processor with nine cores.