TOP500 Marks 25th Anniversary with a Major Shakeup at the Top

Coinciding with the International Supercomputing Conference, the TOP500 List of supercomputers has been announced. For the first time since November 2012, the U.S. claimed the most powerful supercomputer in the world, leading a significant turnover in which four of the five top systems were either new or substantially upgraded. With the announcement, the TOP500 is also marking its 25th anniversary.

The first version of what became the current TOP500 list started as an exercise for a small conference in Germany in June 1993. Since then the list has continued and is now a much-anticipated twice-yearly event in June and November.

The TOP500 list is compiled by Erich Strohmaier and Horst Simon of Lawrence Berkeley National Laboratory; Jack Dongarra of the University of Tennessee, Knoxville; and Martin Meuer of ISC Group, Germany.

Summit, an IBM-built supercomputer now running at the Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL), captured the number-one spot on the new list with a performance of 122.3 petaflops on High Performance Linpack (HPL), the benchmark used to rank the TOP500 list. Summit has 4,356 nodes, each one equipped with two 22-core Power9 CPUs, and six NVIDIA Tesla V100 GPUs. The nodes are linked together with a Mellanox dual-rail EDR InfiniBand network.

Sunway TaihuLight, a system developed by China’s National Research Center of Parallel Computer Engineering & Technology (NRCPC) and installed at the National Supercomputing Center in Wuxi, came in at number two after leading the list for the past 2 years. Its HPL mark of 93 petaflops has remained unchanged since it came online in June 2016.

Sierra, a new system at the DOE’s Lawrence Livermore National Laboratory took the number-three spot, delivering 71.6 petaflops on HPL. Built by IBM, the Top500 creators note that Sierra’s architecture is similar to that of Summit, with each of its 4,320 nodes powered by two Power9 CPUs plus four NVIDIA Tesla V100 GPUs and using the same Mellanox EDR InfiniBand as the system interconnect.

Tianhe-2A, also known as Milky Way-2A, was in the number-four spot, despite receiving a major upgrade that replaced its 5-year-old Xeon Phi accelerators with custom-built Matrix-2000 coprocessors. The new hardware increased the system’s HPL performance from 33.9 petaflops to 61.4 petaflops, while bumping up its power consumption by less than four percent. Tianhe-2A was developed by China’s National University of Defense Technology (NUDT) and is installed at the National Supercomputer Center in Guangzhou, China.

The new AI Bridging Cloud Infrastructure (ABCI) is the fifth-ranked system on the list, with an HPL mark of 19.9 petaflops. The Fujitsu-built supercomputer is powered by 20-core Xeon Gold processors along with NVIDIA Tesla V100 GPUs. It’s installed in Japan at the National Institute of Advanced Industrial Science and Technology (AIST).

Piz Daint (19.6 petaflops), Titan (17.6 petaflops), Sequoia (17.2 petaflops), Trinity (14.1 petaflops), and Cori (14.0 petaflops) were in the number six-through-10 spots, respectively.

According to the list’s creators, accelerators are used in 110 TOP500 systems, a slight increase from the 101 accelerated systems in the November 2017 lists.

NVIDIA GPUs are present in 98 of these systems, including five of the top 10: Summit, Sierra, ABCI, Piz Daint, and Titan.

“The new TOP500 list clearly shows that GPUs are the path forward for supercomputing in an era when Moore’s Law has ended,” said Ian Buck, vice president and general manager of accelerated computing at NVIDIA. “With the invention of our Volta Tensor Core GPU, we can now combine simulation with the power of AI to advance science, find cures for disease and develop new forms of energy. These new AI supercomputers will redefine the future of computing.”

“This year’s TOP500 list represents a clear shift toward systems that support both HPC and AI computing,” said Jack Dongarra, professor at the University of Tennessee and Oak Ridge National Laboratory, who co-authors the TOP500 list. “Accelerators, such as GPUs, are critical to deliver this capability at the performance and efficiency targets demanded by the supercomputing community.”

In addition, the Top500 creators note, seven systems are equipped with Xeon Phi coprocessors, while PEZY accelerators are used in four systems. An additional 20 systems now use Xeon Phi as the main processing unit.

Almost all the supercomputers on the list (97.8%) are powered by main processors with eight or more cores and more than half (53.2%) have over 16 cores.

Ethernet, 10G or faster, is now used in 247 systems, up from 228 6 months ago. InfiniBand is found on 139 systems, down from 163 on the previous list. Intel’s Omni-Path technology is in 38 systems, slightly up from 35, 6 months ago.