The most powerful supercomputer in Europe is being built in Jülich. An innovative building concept allows the JUPITER exascale supercomputer to be flexibly modified.
A significant date for Forschungszentrum Jülich was 15 June 2022. On this day, the European supercomputing initiative EuroHPC JU decided that Europe’s first exascale-class high-performance computer will be built in Jülich. At the Jülich Supercomputing Centre (JSC), Benedikt von St. Vieth heads the department that is responsible for setting up and operating the gigantic computing machines.
The new addition, JUPITER, is set to be inaugurated this winter, explains the expert: “We’re talking about an exascale computer. It can perform one quintillion floating-point operations per second. This is a 1 with eighteen zeros. You would need the equivalent of ten million notebooks for that. To date, there are only two publicly known computer in this performance class, both of which are located in the USA.”
Initial planning for an exascale computer at Jülich began in 2019. However, when the decision was made three years later, conditions had changed: “As a result of the pandemic and the invasion of Ukraine, prices and, therefore, construction costs had exploded,” recalls von St. Vieth. This meant that the previous concept for the data centre designed to house the new supercomputer was up for discussion.
The original plan was to erect a multi-storey building. A central infrastructure would have supplied JUPITER with electricity and cooling water. However, it was not only the costs that now spoke against such a standard solution, but also the tight time frame in which it was due to be put into operation. “That’s why we decided against building a traditional data centre, instead opting for a modular building in a container design. It’s quicker and less expensive,” says von St. Vieth.
Particularly Suitable for AI
JUPITER enables scientists to calculate simulations in greater detail than ever before, whether it be comprehensive calculations for climate research, fluid mechanics, or molecular dynamics. AI algorithms have an important role to play here, says Prof. Thomas Lippert, director of the Jülich Supercomputing Centrer: “JUPITER will be ideally suited for artificial intelligence applications.” At the core of JUPITER is a booster module with around 24,000 GPUs (graphics processing units) from NVIDIA, which are specially tailored to AI applications. This is supported by a cluster module that is suitable for universal tasks. Thanks to the modular system architecture, which was developed as software at Jülich several years ago, both components can also work hand in hand and thus perform particularly efficient calculations.
The basic structure of the supercomputer has not been changed as a result of the new design. The installation will cover an area that equates to roughly half a football pitch. It will consist of around 50 containers, which will be manufactured and supplied by the IT company Eviden (Atos Group). At first glance, the containers resemble the metal boxes from cargo ships, says the expert: “But they are custom-made designs with excess lengths. Two containers are always combined to form one IT module. This dual container comprises 20 computer racks. These are the frames in which the more than 7,000 servers are housed.” Each module has its own transformers for the power supply and its own cooling infrastructure – a sustainable hot water cooling system. The water heats up from 36 to over 40 degrees Celsius. The thermal energy can be used via a heat exchanger to supply heating systems on campus, for example.
“We are now convinced that we are leading the way with the modular design of JUPITER,” says von St. Vieth. “Of course, the container design might also have disadvantages in terms of exposure to nature. It could be penetrated by rainwater. But we don’t think that will be a problem.” The advantage of the modular design is that it enables a high degree of flexibility. Individual containers can be replaced relatively easily to optimize the overall system to meet new requirements. Von St. Vieth: “The next computer generation with significantly higher requirements could be easily integrated into the overall architecture on a module-by-module basis. Conventional data centres that were built 10 to 20 years ago, on the other hand, reach their capacity limits in terms of power supply and heat dissipation with such expansion measures.”
The container design also enables the integration of modules based on completely different computing technology in future. This might be quantum computers or neuromorphic systems that are inspired by the way the human brain works, explains von St. Vieth: “At present, such alternative concepts that go beyond binary computing are not planned for JUPITER. However, if such a module were to be built, it could easily be integrated using the container design. Not bad for a concept that was originally intended as an emergency solution.”
Text: Arndt Reuning | image (second from the top): Forschungszentrum Jülich/Sascha Kreklau
