For the fourth consecutive time, Tianhe-2, a supercomputer developed by China’s National University of Defense Technology, has retained its position as the world’s number one system. Meanwhile, Titan at Oak Ridge National Laboratory, which was the top supercomputer in November 2012, remains number two.
Tianhe-2 is capable of performing at 33.86 petaflops, or 33.86 quadrillions of calculations per second, on a benchmark test known as Linpack.
The rankings are from the 44th edition of the twice-yearly TOP500 list of the world’s most powerful supercomputers, which was announced Monday in Mannheim, Germany; Berkeley, California; and Knoxville. Tianhe-2 has been in the top spot four consecutive times, and Titan has been number two each time.
“In fact, there was little change among the ranking of the world’s top 10 supercomputers in the latest edition of the closely watched list,” according to a press release on the TOP500 website.
Separately, though, U.S. officials on Friday announced a partnership between the U.S. Department of Energy’s Oak Ridge Leadership Computing Facility and IBM to produce a a hybrid computing system called Summit. That new supercomputer is expected to be delivered in 2017, and officials said it will have five times the performance of Titan.
The only new entry on Monday’s Top500 list was at number 10—a 3.57 petaflop Cray CS-Storm system installed at an undisclosed U.S. government site.
A detailed analysis of the latest TOP500 list will be presented Tuesday, November 18, at the SC14 conference in New Orleans. At that time, the full list will also be published at TOP500.org, the press release said.
Although the United States remains the top country in terms of overall systems with 231, this number is down from 233 in June 2014 and down from 265 on the November 2013 list. The U.S. is nearing its historical low number on the list.
The number of European systems rose to 130, up from 116 last June, while the number of systems across Asia dropped from 132 to 120. The number of Chinese systems on the list also dropped, now at 61, compared to 76 in June 2014. Over the same period, Japan increased its number of systems from 30 to 32.
Here is more information from the press release:
Slowing trend in performance growth
Since its inception in June 1993, the TOP500 list has served as a consistent measure of the performance growth of supercomputers, since all systems are ranked according to performance running the same Linpack benchmark application. With the latest list, the overall list-by-list growth rates of performance continues to be at historically low values for the last two years.
This lag in the overall average performance of all 500 systems is noticeably influenced by the very large systems at the top of the list. Recent installations of very large systems—up to June 2013—have counteracted the reduced growth rate at the bottom of the list, but with few new systems at the top of the past few lists, the overall growth rate is now slowing. This offers an indication that the market for the very largest systems might currently behave differently from the market of mid-sized and smaller supercomputers.
This is supported by the fact that the performance of the last system on the list (No. 500) has consistently lagged behind historical growth trends for the past five years, a trajectory that now increases by 55 percent each year. Between 1994 and 2008, however, the annual growth rate for the No. 500 systems’ performance was 90 percent.
On the latest edition of the list, the No. 500 system recorded a performance of 153.6 teraflops (trillions of calculations per second), compared with 133.7 teraflops six months ago. The last system on the newest list was listed at position 421 in the previous TOP500. This represents the lowest turnover rate in the list in two decades.
Other highlights from the 44th list
Total combined performance of all 500 systems has grown to 309 petaflops, compared to 274 petaflops in June and 250 petaflops one year ago. This increase in installed performance also exhibits a noticeable slowdown in growth compared to the previous long-term trend. There are 50 systems with performance greater than one petaflops on the list, up from 37 six months ago.
The No. 1 system, Tianhe-2, and the No. 7 system, 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.
A total of 75 systems on the list are using accelerator/co-processor technology, up from 62 from November 2013. Fifty of these use NVIDIA chips, three use ATI Radeon, and there are now 25 systems with Intel MIC technology (Xeon Phi). Intel continues to provide the processors for the largest share (85.8 percent) of TOP500 systems.
Ninety-six percent of the systems use processors with six or more cores, and 85 percent use eight or more cores.
HP has the lead in systems with 179 (36 percent) compared to IBM with 153 systems (30 percent). HP had 182 systems (36.4 percent) six months ago, and IBM had 176 systems (35.2 percent) six months ago. In the system category, Cray remains third with 62 systems (12.4 percent).
About the TOP500 List
The first version of what became today’s TOP500 list started as an exercise for a small conference in Germany in June 1993. Out of curiosity, the authors decided to revisit the list in November 1993 to see how things had changed. About that time they realized they might be on to something and decided to continue compiling the list, which is now a much-anticipated, much-watched, and much-debated twice-yearly event.
The TOP500 list is compiled by Erich Strohmaier and Horst Simon of Lawrence Berkeley National Laboratory; Jack Dongarra of the University of Tennessee in Knoxville; and Martin Meuer of Prometeus, Germany.