Japan tops supercomputer rankings (June 2011)

A supercomputer in Japan hasn't been number 1 since late 2004. Japan had even dropped out of the top 10 list for much of those 7 years. However, a supercomputer that Fujitsu built for Riken (a group of government-funded research institutions) recently put Japan back at the very top. US dominance of petaflop-level computing continues. However, China shows growing strength at supercomputers. This is now an era of PETAFLOP computing, with all top ten computers attaining that level of calculating power.  

http://www.top500.org/lists/2011/06/press-release

excerpt (entire article at link above)

Japan Reclaims Top Ranking on Latest TOP500 List of World’s Supercomputers
Thu, 2011-06-16 19:24


HAMBURG, Germany. A Japanese supercomputer capable of performing more than 8 quadrillion calculations per second (petaflop/s) is the new number one system in the world, putting Japan back in the top spot for the first time since the Earth Simulator was dethroned in November 2004, according to the latest edition of the TOP500 List of the world’s top supercomputers. The system, called the K Computer, is at the RIKEN Advanced Institute for Computational Science (AICS) in Kobe.
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For the first time, all of the top 10 systems achieved petaflop/s performance-- and those are also the only petaflop/s systems on the list. The U.S. is tops in petaflop/s with five systems performing at that level; Japan and China have two each, and France has one.

Bumped to second place after capturing No. 1 on the previous list is the Tianhe-1A supercomputer the National Supercomputing Center in Tianjin, China, with a performance at 2.6 petaflop/s. Also moving down a notch was Jaguar, a Cray supercomputer at the U.S. Department of Energy’s (DOE’s) Oak Ridge National Laboratory, at No. 3 with 1.75 petaflop/s.