The astrophysics "N-body problem" consist in a dynamical N celestial bodies model which interact gravitationally.
Solving this problem implies understand and predict the movement of the system components, for example, the Solar System, a stars cumulus, or a galaxy.
To systems with more than 3 bodies, which are most of the interesting astronomical systems, the problem do not have an analytic solution, and it is necessary to use computational methods, which are progresively more expensives to largest values of N.
GraviDy is a new GPU, direct-summation N-body integrator written from scratch and based on the Hermite scheme. The most important features of the code are:
- Written in C/C++,
- Using parallel computing techniques and libraries like OpenMP, MPI and CUDA,
- full double-precision resolution,
- its high modularity, which allows users to readily introduce new physics into it,
- the exploitation of all high-performance computing resources available,
- its maintenance and improvement cycle,
- the fact that the code is publicly released under a BSD license and will be maintained via planned, public, regular updates.
Maureira-Fredes, C and Amaro-Seoane, P. "GraviDy, a GPU modular, parallel direct-summation N−body integrator: Dynamics with softening", MNRAS, vol. 473, pp. 3113-3127, Jan . 2018.
| Software | Version | Description |
|---|---|---|
| GCC | v4.4.7 or greater | Compiler |
| boost::program_options | v1.52.0 or greater | command-line options |
| OpenMPI | v1.8.8 or greater | MPI implementation |
| CUDA | v5.5 or greater | GPU implementation |
Enter the src directory and proceed to edit the Makefile with the Boost, CUDA and OpenMPI paths if they are not installed on the system, otherwise the flags are not needed.
Every version can be generated by:
- CPU version
make pn
- MPI version
make mpi
- GPU version
make gpu
The example initial conditions are in a different git respository, that it can be cloned through the setup-submodule script, in the root of the repository.
If you do not have a Gitlab account, you can clone the repository directly:
git clone https://gitlab.com/cmaureir/gravidy-input.git
Copyright 2014 Cristián Maureira-Fredes
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