The K computer has taken first place in the HPCG benchmark, a new index of supercomputing performance intended to create a more realistic view of supercomputers compared to the commonly used LINPACK benchmark.
The High Performance Conjugate Gradients (HPCG) Benchmark project is an effort to create a new metric for ranking HPC systems. The benchmark is intended to complement to the High Performance LINPACK (HPL) benchmark, currently used to rank the TOP500 computing systems.
Kimihiko Hirao, director of the RIKEN Advanced Institute for Computational Science, stated: ‘Combined with the fact that the K computer took seventh place on the TOP500 list and first place on the Graph 500 list this year, this achievement demonstrates the high performance of our supercomputer in general applications, making it a powerful tool for industrial and scientific applications in a wide range of fields.’
HPCG is designed to exercise computational and data access patterns that more closely match a different and broad set of important applications, and to give an incentive to system designers to invest in capabilities that will increase the collective performance of these applications.
For this competition, all of the K computer’s 82,944 compute nodes were used to achieve a performance of 602 teraflops, a score much higher than the 461 teraflops it reached when taking second place in 2014. This new, increased figure demonstrates performance higher than many of the supercomputers that placed higher than the K computer in the TOP500 rankings – demonstrating outstanding, sustained application performance.
Ultimately, the benchmark measures how fast a computer can solve symmetric sparse linear system equations using the conjugate gradient method preconditioned with a multi-grid symmetric Gauss-Seidel smoother. Problems of this type are typically encountered in actual engineering and industrial applications, and require a balance between calculation performance, memory performance and communication performance, unlike LINPACK, which looks at calculation speed alone.
Jack Dongarra, of the University of Tennessee, who developed the benchmark, said: ‘The K computer is number one on the HPCG list, showing that a well-balanced architecture with a good floating point rate and a good memory transfer rate allows high performance for a wide range of scientific applications.’
In addition to the K computer taking the top spot, the Chinese ‘Tianhe-2’ took second place – and a second Fujitsu system, ‘Oakforest-PACS’, housed at the Joint Center for Advanced High Performance Computing in
Japan, took the third spot.
More information on the HPCG benchmark results can be found here.
RIKEN is Japan's largest research institute for basic and applied research. The centre provides a research environment with strong emphasis on interdisciplinary collaboration and globalisation which has led to the centre establishing its place as one of the foremost institutes for HPC and scientific research.