With a performance of 33.86 petaflop/s (quadrillions of calculations per second) on the Linpack benchmark, Tianhe-2, a supercomputer developed by China’s National University of Defense Technology (Changsha, China), has retained its position as the world’s No. 1 supercomputer, according to the 43rd edition of the twice-a-year TOP500 list. The Linpack benchmark requires a computer to solve a dense system of linear equations.
In second place was Titan, a Cray supercomputer based at the Department of Energy’s Oak Ridge National Laboratory.
The survey marked the fifth consecutive six-month period that China’s Tianhe-2 computer has topped the list, and the sixth time overall since 2010 that a Chinese machine has been designated number one.
The United States remains the top country in terms of overall systems represented on the list with 233, down from 265 in November 2013. The number of Chinese systems on the list rose from 63 to 76, and Japan increased its showing, up to 30 from 28 on the previous list.
Sixty-two systems on the list are using accelerator/co-processor technology, up from 53 in November, 2013. Forty-four of these use NVIDIA chips, two use ATI Radeon, and there are now 17 systems with Intel Xeon Phi technology. The average number of accelerator cores for these 62 systems is 78,127 cores/system. The No. 1 system, Tianhe-2, and the No. 7 system on the list, Stampede, use Intel Xeon Phi processors to speed up their computational rate. The No. 2 system, Titan, and the No. 6 system, Piz Daint, use NVIDIA GPUs to accelerate computation. Intel continues to provide the processors for the largest share (85.4 percent) of TOP500 systems. The number of supercomputers on the list using IBM Power processors remains at 8 percent, while the AMD Opteron family is used in 6 percent of the systems, down from 9 percent on the previous list.
HP has the lead in systems and now has 182 systems (36 percent) on the list compared to IBM with 176 systems (35 percent). Cray remains third with 10 percent (50 systems).
Ninety-six percent of the systems use processors with six or more cores and 83 percent use eight or more cores.
The rate of performance development for supercomputers seems to be slowing. The TOP500 organizers confirm that the last two years have seen historically low year-over-year performance increases.