One of the biggest benefits of the inexorable push toward exascale computing is a coming age of more affordable petascale systems. This trend can already be seen as science centers around the world crest this important barrier. One of the latest to do so is the Center for Computational Astrophysics (CfCA) of the National Astronomical Observatory of Japan (NAOJ), which recently announced a major upgrade to its Cray XC30 system, called “ATERUI.” With beefed-up Intel CPUs under the hood, ATERUI’s theoretical peak performance shot up from 502 teraflops to 1.058 petaflops, doubling its speed and enabling researchers to tackle ever bigger questions about the universe and space.
Simulating cosmic puzzles is ATERUI’s raison d’etre, and even at a half-petaflop, the massively parallel supercomputer was considered to be the world’s fastest supercomputer devoted to astronomical simulation. The invigorated supercomputer will further fortify the center’s astronomical simulations.
ATERUI was taken offline from September 11th-30th, 2014, in order to switch out its Intel Xeon E5-2670 processors to the newest-generation Intel Xeon E5-2690 v3 parts. Main memory was also goosed: from 94.25 terabytes to 135.6 terabytes. With 12-core chips replacing 8-core variants, compute power per node ballooned from 332 gigaflops to 998 gigaflops as the number of nodes fell: from 1,512 to 1,060. The increased density trimmed ATERUI’s rack count from eight to six. Total core count went up slightly: from 24,192 to 25,440.
“Supercomputers for astronomical researches can be called ‘telescopes for theoretical astronomy’ because they illustrate astrophysical phenomena that telescopes cannot see. New visions of the Universe which have never been seen before will be revealed by more realistic simulations using the new ATERUI,” states CfCA Project Director Professor Eiichiro Kokubo.
The importance of numerical simulation is such that it is now considered a third leg of astronomical research, according to NAOJ, taking residence alongside observational and theoretical astronomy. Consider how enormous spatial and time scales hampering the ability to reconstruct astronomical phenomena in a laboratory. Theoretical astronomy attempts to understand the universe with equations that when large enough require the power of supercomputers. Simulation astronomers make models of elements of the universe, and check their accuracy by comparing them with actual observations. ATERUI is NAOJ’s fourth major dedicated system but the need for regular upgrade paths will remain strong as long as astronomical research keeps pushing at the limits of supercomputing.
The punched-up system came back online October 1, 2014, and has already served 127 researchers and graduate students from NAOJ. It is also available to other Japanese researchers both in Japan and abroad. The simulations that ATERUI has performed extend to the birth of planets, the creation and death of stars, solar activity, black holes, and large-scale galactic happenings. Many of these simulations require immense computing power, especially when high-energy physics is involved. The new ATERUI will make it possible to tackle more complex simulations with added resolution. It will also allow the utilization of smaller time steps, so this amazing phenomenon is more fully revealed. Whether it’s the motions of the stars or the structure of galaxies or the very universe itself, the new ATERUI will provide a clearer picture of the farthest reaches of the cosmos.