GENCI’s OCCIGEN supercomputer

OCCIGEN, pushing the frontiers of science and technology

GENCI's OCCIGEN supercomputerWith its new large scale supercomputer called OCCIGEN (pronounced oxygen), GENCI, the French HPC agency, provides French scientists with a great boost of the global capacity available and makes a technological leap toward energy efficiency with Bull and Intel.

GENCI, the French HPC agency, has acquired in June 2014 a new 2.1 Pflops large scale supercomputer called OCCIGEN (pronounced oxygen). This Bull system is installed at the National Computer Center for Higher Education (Cines, Centre informatique national de l’enseignement supérieur), one of the three national computing centers in France.

It multiplies by more than 8 times the computing resources available at Cines and allows GENCI to provide French scientists with a great boost of the global capacity available reaching a total of 5.7 Pflops.

Addressing any kind of simulation

OCCIGEN is powered by the 12 cores Intel® Xeon® E5-2690 v3 processor, for a total amount of 50 000 cores and its balanced architecture includes more than 200 TB of distributed memory and an I/O subsystem able to manage data at a speed of over 100GB/s, using Intel supported Lustre* software.

Thanks to this performance, OCCIGEN will be capable of addressing any type of numerical simulation and managing massive amounts of data. It is also designed to subsequently accommodate hybrid technologies

Going green

Bull, an Atos company, has been selected after an open and highly competitive tendering process, including a considerable focus on energy optimization for simulations and financial assessment taking into account the total cost of ownership of the supercomputer over its entire expected lifespan.

Based on the direct liquid cooled bullx B720 compute blades, the OCCIGEN supercomputer has a peak compute performance in excess of 2 PFlops (2 million billion floating point operations per second), implementing the new Intel® Advanced Vector Extensions 2 (Intel AVX2) instruction set, thanks to the Intel® Xeon® processor E5 v3 product family. OCCIGEN reached a « Linpack » performance of more than 1.628 Pflops, thus demonstrating an efficiency rate of 97% of the AVX2 performance per compute node, and of more than 78% of the global system peak performance.

“The OCCIGEN supercomputer powered by the new Intel Xeon E5-2600 v3 product family is a powerful solution for the HPC community, “ said Charles Wuischpard, vice president Data Center Group and general manager of Workstations and HPC, Intel. “The Intel Xeon E5-2690 v3 processor chosen by GENCI for OCCIGEN, offers Top 500 class performance and energy efficiency for the French academic community. This program is part of a long term collaboration between GENCI, Bull and Intel, and a first step to highly parallel workload.”

“OCCIGEN is therefore positioned as one of the most energy-efficient x86 supercomputers (global consumption of 975kW, i.e. 1,670 Mflops/W per node) and is an outstanding addition to the HPCG list of bullx supercomputers with a performance of 45474.6 GFlops. It is now one of the most efficient HPC systems both in terms of performance and energy-efficiency, and a key asset for French digital simulation and research” declared Pascal Barbolosi, VP Extreme Computing at Bull, an Atos company.

World premieres expected

OCCIGEN is aimed to address the needs of French scientists by performing massive 3D multi-scale, multi-physics complex simulations and managing huge amount of data generated by large-scale instruments or numerical simulations.

And, as a first and great result, OCCIGEN has already demonstrated its performances on real scientific key applications with impressive improvements of more than 20% for SPECFEM3D (geophysics) and up to 274% for YALES2 (combustion), in comparison with GENCI current petascale systems.

OCCIGEN will be in full production for all French scientists in January 2015 but is already open in pre-production mode for performing “Grands Challenges” including world premiere in climate modeling, massive LES simulation of wind turbines or brain modeling.

“Our priority is to give to French scientists the means to be in a good position in the international scientific community, by making the best resources available for them, while minimizing the environmental impact. With OCCIGEN, the latest of our supercomputers to be installed, GENCI has completely revamped French computing resources, but is also firmly committed to an eco-responsible approach. The expected OCCIGEN performance will pave the way to great scientific achievements in all fields. ” Catherine Riviere, CEO of GENCI, said.

* Intel, Xeon are trademarks of Intel Corporation in the United States and other countries. Other names and brands may be claimed as the property of others.




Set up in 2007 by the French government, GENCI was created to ensure that France achieves the highest levels in intensive computing, both at an European and international level. With this in mind, GENCI has three main roles: 1) To bring to life the national HPC strategy, to benefit French scientific research in close liaison with the three national computing centers 2) To support the establishment of an integrated HPC ecosystem at a European level 3) To promote the use of computer simulation and HPC in academic and industrial research and, working with Bpifrance and Inria, in a specific initiative aimed at SMEs. GENCI is a legal entity taking the form of a société civile (civil company) under French law, owned 49% by the French State represented by the Ministry for Higher Education and Research, 20% by the CEA, 20% by the CNRS, 10% by the universities and 1% by INRIA, the French national institute for research in computer science and control.