HLRS System Benchmarks

At this place we present information on the benchmarks that will be used among other criteria to rate the proposals for the upcoming procurement of HLRS's next high performance computing system.

User Code Benchmarks

The user code benchmarks include the two computational fluid dynamics (CFD) software packages Flexi and ZFS as well as the molecular dynamics (MD) simulation program ls1 mardyn. The benchmarks are numbered as follows. Please notice that the numbering results from the expected availability of the benchmarks and does not tell anything about the importance of the respective benchmark.

1.) Flexi

This benchmark is based on FLEXI, a high-order numerical framework for solving PDEs, with a focus on Computational Fluid Dynamics. FLEXI is based on the Discontinuous Galerkin Spectral Element Method (DGSEM), which allows for high-order of accuracy and fully unstructured hexahedral meshes.

FLEXI has been developed by the Numerics Research Group lead by Prof. Claus-Dieter Munz at the Institute of Aerodynamics and Gasdynamics at the University of Stuttgart, Germany.

 For further information about the code's general capabilities please see

 2. Zonal Flow Solver - ZFS

This benchmark is based on the Finite-Volume solver of the ZFS software package developed by

 AIA RWTH Aachen

Institute of Aerodynamics

Chair of Fluid Mechanics and Institute of Aerodynamics Aachen

For further details see

3.) ls1 mardyn - ls1

The molecular dynamics (MD) simulation program ls1 mardyn was optimized for massively parallel execution on supercomputing architectures. The acronym stands for large systems 1: molecular dynamics.

With an efficient MD simulation engine, explicit particle-based force-field models of the intermolecular interactions can be applied to length and time scales which were previously out of scope for molecular methods. Employing a dynamic load balancing scheme for an adaptable volume decomposition, ls1 mardyn delivers a high performance even for challenging heterogeneous configurations.

Benchmark Distribution

Please be aware that, even though Flexi as well as ls1 are released as open source codes, the versions of the codes used to create the benchmarks are fixed an will be provided by HLRS upon explicit request.

So please do not use any code versions that might be provided via or or any other source.

Additionally, the ZFS code is not released as open source which means that the code packages provided by HLRS may only be used for benchmarking purposes.


In case you have any questions related to the benchmarks please do not hesitate to contact us.

Dr.-Ing. Ralf Schneider
Head of Numerical Methods & Libraries

HLRS - High Performance Computing Center Stuttgart
Nobelstraße 19
70569 Stuttgart - Germany

Phone: +49 711 685 87236