13. July 2023

Sustainable computing for top-level research

TU Darmstadt inaugurates Lichtenberg II high-performance computer

TU Darmstadt officially inaugurated the new Lichtenberg II high-performance computer on Tuesday (July 11). Equipped with the latest technology, it sets standards in performance and energy efficiency and thus offers the best conditions for excellent research. Lichtenberg II is also part of the Network for National High Performance Computing (NHR) and supports the nationwide provision of computing power for science in a particularly sustainable and resource-efficient way. The computer is named after the polymath Georg Christoph Lichtenberg (1742-1799).

State Secretary Ayse Asar, Professor Christian Bischof and TU President Tanja Brühl in front of the new expansion stage of the Lichtenberg II high-performance computer (from left to right).
State Secretary Ayse Asar, Professor Christian Bischof and TU President Tanja Brühl (from left to right). Picture: Klaus Mai

The design of sustainable materials, the management of the energy transition or the security of cyberspace are just a few examples of applications that require data-intensive calculations. The performance of Lichtenberg II enables calculations that could not be performed at all or only much more slowly on ordinary computers. The scientific topics are as diverse as the applications and simulation programs that researchers need to tackle them. The flexible architecture of the Lichtenberg II high-performance computer enables adaptable solutions tailored to the needs of the scientists.

The Lichtenberg II thus creates optimal computing conditions for researchers at TU Darmstadt – also with regard to the upcoming round of the Excellence Strategy of the federal and state governments, for which the TU is applying with five clusters. In addition, the Lichtenberg II system is an important aggregate in the highly efficient energy management concept on the Lichtwiese campus of TU Darmstadt.

State Secretary Ayse Asar of the Hessian Ministry of Science and the Arts (HMWK), together with the President of the TU Darmstadt, Professor Tanja Brühl, officially commissioned the overall Lichtenberg II system today. The high-performance computer, which has a total investment volume of 15 million euros, is the technical heart of a sustainable overall concept consisting of reliable operation, focused consulting and cutting-edge research that translates methodological innovations in the form of first-principle models and data-based simulation programs into new insights.

The Joint Science Conference had advised the federal funding of the high-performance on the basis of a recommendation by the German Council of Science and Humanities in 2017. The Science Council only makes such endorsements for research programs with outstanding scientific quality and of nationwide importance.

State Secretary Asar emphasizes, “The powerful Lichtenberg II high-performance computer opens up excellent opportunities for Hessian universities to tackle complex challenges and find innovative solutions. The competitiveness of the Hessian science landscape will be significantly strengthened as a result. In this respect, the inauguration is a great success for the TU Darmstadt and for the state of Hesse. For NHR4CES, the National High Performance Computing for Computational Engineering Sciences, the federal government and the state of Hesse are providing 28 million euros until 2024. In addition, Hessian AI, the Hessian Center for Artificial Intelligence, will receive 38 million euros in funding from the state of Hesse. Also, 112 million euros will be made available for the digital transformation of Hessen’s universities through 2024 via the Digital Pact for Universities.”

“With the new high-performance computer Lichtenberg II, TU Darmstadt disposes of another building block to create excellent conditions for research that seeks answers to socially relevant questions of the future, e.g., on climate change, energy transition or resource use, with the help of computationally intensive methods,” says Professor Dr. Tanja Brühl, President of Technische Universität Darmstadt. “I am pleased that we can provide the scientists of the TU Darmstadt and other Hessian and nationwide research institutions with such a future-oriented computer system, which meets the most modern demands for efficiency and sustainability, in an energetically optimized building.”

Networking with other high-performance computing centers

Collaboration and networking among high-performance computing centers will increase efficiency and access to powerful computing infrastructure for scientists throughout Germany. “TU Darmstadt is one of nine centers of the National High Performance Computing – NHR -,” explained Professor Christian Bischof from the Department of Scientific Computing in the Department of Computer Science. “The NHR4CES – NHR for Computational Engineering Sciences – center, which TU Darmstadt is driving together with the NHR center at RWTH Aachen University, supports the simulation of technical products that are of central importance for developments in industry and society.” The focus of NHR4CES at TU Darmstadt is on engineering and materials sciences as well as engineering-oriented physics and chemistry, he said. Methodological approaches such as numerical simulation or artificial intelligence would be dovetailed with integrated solutions for high-performance computing and research data management.

Highly efficient energy management concept

Energy-efficient computer systems and sustainable use are key goals for TU Darmstadt. For this reason, the waste heat from Lichtenberg II is not simply released into the environment, but during the heating period, a significant portion is fed into the district heating network that connects all buildings on the Lichtwiese campus.

For this purpose, Lichtenberg II uses direct and highly efficient hot water cooling to fully utilize the power of the processors. In the process, special heat exchangers and coolant distributors enable high return temperatures of more than 45 degrees Celsius to ensure sensible reuse of energy and efficient cooling. This leads to a significantly improved CO2 and energy balance and is an important step towards sustainable high-performance computing.


The Lichtenberg II system

In mid-2020, the first expansion stage of the Lichtenberg II system with 643 computing nodes was put into operation; this will now be expanded by 581 computing nodes with the second expansion stage. Together, the two expansion stages will provide their users with a theoretical peak performance of approximately 8.5 petaflops (PFlops) per second through processors and 1.7 petaflops per second through accelerators. The main memory totals 563 terabytes, the storage system for data around 6 petabytes.

The Lichtenberg supercomputer, which is operated by the University Computing Center (HRZ) of TU Darmstadt, is one of the fastest university computers in Germany and is represented twice in the current ranking of the Top500 supercomputers worldwide. With its first expansion stage, it is ranked 216th, and with its new (second) expansion stage, it is the winner among the participating Sapphire Rapid systems (4th generation Intel Xeon Scalable processors) and is thus ranked 230th on the list. 

The investment costs for the Lichtenberg high-performance computer of 15 million euros are borne in equal parts by the federal government and the state of Hesse.