The U.S. once again has the most powerful supercomputer in the world, thanks to the U.S. Department of Energy's Sequoia, according to the latest edition of the Top500 supercomputer list, ending Asia's hold on the top spot. Sequoia's 1.57 million processor cores can perform 16.32 petaflops (quadrillion floating-point calculations per second).
Chinese Tianhe-1A supercomputer in November 2010. That, in turn, was surpassed by the Japanese K Computer, which held on to the number one spot for two editions of the twice yearly list. The K Computer, able to perform 10.51 petaflops on its 705,024 Sparc64 processing cores, is now in second place, while Tianhe-1A has slipped to fifth place.
Sequoia is an IBM BlueGene/Q system powered by Power BQC 16-core processors running at 1.6GHz. It runs Linux. The DOE's National Nuclear Security Administration announced Sequoia's construction in February 2009. The computer is installed at the Lawrence Livermore National Laboratory, and has been upgraded since it appeared at 17th place in last November's ranking.