During the 2013 NVIDIA GPU Technology conference, the Swiss National Supercomputing Center (CSCS) revealed that its Cray XC30 “Piz Daint” supercomputer was on track to becoming Europe’s fastest GPU-accelerated number-cruncher, and the first Cray machine to be equipped with Intel Xeon processors and NVIDA GPUs. Now, one year later, the revved-up Piz Daint is officially cleared for research.

On March 21, Fritz Schiesser, the president of the ETH Board, Ralph Eichler, the president of ETH Zurich, and luminaries from research, politics and industry gathered together in Lugano to inaugurate the upgraded Piz Daint – the flagship Swiss supercomputer that is the fastest in Europe.

Prof. Dr. Ralph Eichler, Prof. Dr. Thomas Schulthess and Dr. Fritz Schiesser

Named for one of the highest mountains in the Swiss Alps, Piz Daint was built by the Swiss National Supercomputing Center (CSCS) to provide scientists with extreme-scale computing resources for a wide variety of disciplines, including climate science, geoscience, chemistry, physics, biology, and materials research. The center has particularly emphasized the expected benefit for its weather and climate modeling work.

According to Thomas Schulthess, director of CSCS, the new and improved Piz Daint enables a weather prediction application to run three times faster with seven times less energy compared to its predecessor, the CPU-only “Monte Rosa.” The hybrid Piz Daint is also expected to improve energy-efficiency by a factor of three compared to GPU-less version.

Piz Daint was built and configured in the fall of 2013 in time for the latest TOP500 and the Green 500 lists that were published in November 2013. Within the coveted top 10 zone of each of these lists, Piz Daint is only machine that appears on both – where it is the sixth most powerful and the fourth most energy-efficient, respectively. In addition to nabbing this double honor, Piz Daint is also one of only two petafloppers to crack the top 10 on the Green 500.

With the upgrade, Piz Daint ballooned from twelve computer cabinets to twenty-eight, stuffed with a mix of Intel Xeon E5 processors and NVIDIA Tesla K20X GPUs. The number of compute nodes increased from 2,256 to 5,272 tightly bound by Cray’s Aries interconnect. The system touts 6.2 petaflops of performance as measured by the LINPACK Benchmark and reaches a theoretical peak performance of 7.8 petaflops.

In terms of energy efficiency, Piz Daint with 3.2 gigaflops per watt was the first petascale-class system to break the 3 gigaflop per watt barrier. The combination of GPUs and CPUs helped make Piz Daint the most energy-efficient supercomputer in the petaflop club.

To secure approval from manufacturer Cray, the renovated Piz Daint has been put through its paces.

“Thanks to the close and dedicated collaboration between hardware producers, researchers and CSCS staff, we have succeeded in opening ‘Piz Daint’ up for research in record time after the upgrade,” says Schulthess in a statement.

Scientists from all disciplines can apply for computer time on Piz Daint every six months through the regular CSCS user program. For larger projects, CHRONOS puts out an annual call for proposals. Computer time is allocated by an independent committee of specialists.

Schulthess highlighted the fact that natural sciences cannot be satisfied solely with more powerful supercomputers; investments also need to be made to advance computing algorithms and software. For this reason, the platform for High-Performance and High-Productivity Computing (HP2C) was launched. Under this program, application developers have spent the last four years collaborating with applied mathematicians and computer scientists to create more efficient simulation systems.

Piz Daint is the result of this collaboration. “For the first time at CSCS, a new supercomputing system has been co-designed along with key scientific application codes,” Schulthess  states. “Building the hybrid ‘Piz Daint’ supercomputer in such a short time was only possible thanks to an excellent collaboration with Cray, NVIDIA, and application scientists at Swiss universities.”