China scoops the Top500 again
As was widely expected, Tianhe-2, the supercomputer developed by China’s National University of Defence Technology, has retained its position as the world’s No. 1 system for the fifth consecutive time.
The ranking was foreshadowed in an article just published in the most recent issue of Scientific Computing World How do you measure a supercomputer's speed? and was officially confirmed by the 45th edition of the twice-yearly Top500 list of the world’s most powerful supercomputers published today at the European supercomputing conference, ISC High Performance.
Tianhe-2, which means Milky Way-2, led the list with a performance of 33.86 Petaflops on the Linpack benchmark. This is about twice the performance of the second-ranking machine, Titan, a Cray XK7 system installed at the US Department of Energy’s (DOE) Oak Ridge National Laboratory. Titan, the top system in the United States and one of the most energy-efficient systems on the list, achieved 17.59 Petaflops on the Linpack benchmark.
The only new entry in the Top 10 supercomputers on the latest list was in seventh place: Shaheen II, a Cray XC40 system installed at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia. Shaheen II achieved 5.536 Petaflops on Linpack, making it the highest-ranked Middle East system in the 22-year history of the list and the first to crack the Top 10.
The other nine systems in the top 10 were all installed in 2011 or 2012, and this low level of turnover among the top supercomputers reflects a slowing trend that began in 2008.
Although the United States remains the top country in terms of overall systems with 231 (the same as the last list in November 2014), this number is down from 233 in June 2014 and down from 265 on the November 2013 list. The US is nearing its historical low number on the list.
The total combined performance of all 500 systems has grown to 361 Pflops, compared to 309 Pflops last November and 274 Pflops one year ago. This increase in installed performance also exhibits a noticeable slowdown in growth compared to the previous long-term trend. There are 67 systems with performance greater than 1 Petaflops on the list, up from 50 last November.
The most powerful system, Tianhe-2, and the eighth, Stampede at Texas, use Intel Xeon Phi co-processors to speed up their computational rate. The second system, Titan, and the sixth, Piz Daint in Switzerland, use Nvidia GPUs to accelerate computation.
A total of 88 systems on the list are using accelerator/co-processor technology, up from 75 in November 2014. Forty-nine of these use Nvidia chips, four use ATI Radeon, and there are now 29 systems with Intel MIC technology (Xeon Phi). Intel continues to provide the processors for the largest share (86.2 percent) of TOP500 systems.
Ninety-seven percent of the systems use processors with six or more cores and 87.8 percent use eight or more cores.
HP has the lead in the total number of systems with 177 (35.4 percent) compared to IBM with 108 systems (21.6 percent). Last November, HP had 179 systems and IBM had 153 systems. In the system category, Cray remains third with 71 systems (14.2 percent).