Interview: Authors Discuss HPC@Green IT

In this interview, Ralf Gruber and Vincent Keller, the authors of HPC@Green IT discuss what prompted them to write the book and the feedback they’ve gotten from their peers at SC10.

In the US computing centres are built with up to 25 MW electric power. In Switzerland, the CSCS is planning a new centre with a few MW installed. And this trend continues, one already talks about the exaflop (one exaflop per second: 1 EF/s = 1018 operations per second) machine in 2018. Consider that each node in a parallel machine consumes today about 200 Watts, half for the processor, half for the main memory subsystem. Such a node delivers perhaps 200 GF/s thanks to an increasing number of cores. To reach one EF/s, millions of such nodes must be put together. This would lead to a power consumption comparable to a nuclear power plant. Do we really need an exaflop machine? Or should we rather build computers that are adapted to HPC application needs, and, as a consequence, consume much less energy? I believe that Switzerland could be the first country to do so.