Published December 18, 2025 | Version v1

Plasma-PEPSC D1.13 Updated Assessment of Developments and Revision of Scientific Challenge, Predicting Near-Earth Space Dynamics with Vlasiator

  • 1. ROR icon University of Helsinki

Contributors

Project leader:

Work package leader (2):

  • 1. ROR icon KTH Royal Institute of Technology
  • 2. ROR icon Max Planck Computing and Data Facility

Description

In this deliverable, we provide an update of the progress for the Vlasiator plasma simulation code, in terms of its development progress towards the scientific target case within Plasma-PEPSC. It gives an outline of the basic physical environment and state of the art of near-Earth plasma simulations that Vlasiator performs, and reiterates the scientific target case which would be desirable to simulate within the timeframe of this EuroHPC project. Performance profiling results of Vlasiator have been updated at various scales, and their results are being presented, in direct comparison to the earlier results from deliverable D1.4.

Based on the profiling data, performance extrapolation to the scientific target case shows that Vlasiator currently has a performance gap of a factor 32 compared to what would be required, down from the initial gap value of 52 at the beginning of the project. We discuss further steps in the development of the simulation code to address this gap, and give an overview of the planned improvements to the code.

Files

D1.13_Updated_assessment_of_developments_and_revision_of_Vlasiator_scientific_challenge-Vlasiator.pdf

Additional details

Funding

European Commission
Plasma-PEPSC - Plasma Exascale-Performance Simulations CoE - Pushing flagship plasma simulations codes to tackle exascale-enabled Grand Challenges via performance optimisation and codesign 101093261

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