Proceedings 2023 ESPResSo meetings

Proceedings of the 2023 ESPResSo meetings

2023-02-06

waLBerla integration progress report

• checkpointing now works in parallel
• thermalized electrokinetics is not ready yet
• GPU LB is not ready yet (custom interface needs to be written)

Monte Carlo Python re-implementation

• MC methods were rewritten as Python code by Pablo
• overhead from MPI callbacks in the hot loop (make_reaction_attempt)
• priority is to be able to write the acceptance probability in Python

2023-01-17

Build system changes

• the custom GPU detection code was replaced with native CUDA support from CMake 3.22 (#4642)
• specify the CUDA compiler and toolkit with CUDACXX=/path/to/nvcc cmake .. -D CUDAToolkit_ROOT=/path/to/toolkit

Upcoming 4.2.1 bugfix release

• bugs with high severity:
  • broken checkpointing: LB boundaries, particle director and dipole moment
  • broken reactions when using concurrent reactions that delete particles
  • broken configurational moves in reactions
  • broken Brownian integration of fixed particles
• draft release notes: 4.2.1

Multiscale proposal

• contributions to community codes: LAMMPS, ESPResSo, waLBerla, kinetic lattice models
• deliverables:
  • filesystem-based environments containing dependencies tailored for HPC (EESSI)
  • waLBerla-ESPResSo integration including CUDA kernels
  • refactoring electrostatics algorithms (e.g. replacing MPI FFT by shared memory FFT)

waLBerla integration

• ESPResSo is still missing the CUDA setters and getters (populations, density, etc.)
• ekin checkpointing is a work in progress

Coding day

• planned for mid-February