Making TSUBAME2.0, the world's greenest production supercomputer, even greener — Challenges to the architects

Supercomputers of the past were “performance at all cost” including power consumption, but nowadays supercomputers require even higher power-performance efficiencies than normal computers. For the past 25 years the ratio of supercomputer performance increase has constantly exceeded the so-called “Moore's Law”, but this has been partly achieved by increasing the size and thus the power requirement of the machine; such power increase is no longer viable because the machines have gotten too big. Our new project “JST-CREST ULP-HPC” and the new TSUBAME2.0 supercomputer we have built at Tokyo Institute of Technology aims to obtain utmost power efficiency in HPC. TSUBAME2.0 has been recognized as the “Greenest Production Supercomputer in the World” in the Green 500 rakings in November, 2010.