StePS: A Multi-GPU Cosmological N-body Code for Compactified Simulations
Department of Physics of Complex Systems, Eotvos Lorand University, Pf. 32, H-1518 Budapest, Hungary
arXiv:1811.05903 [astro-ph.CO], (14 Nov 2018)
@article{racz2018steps,
title={StePS: A Multi-GPU Cosmological N-body Code for Compactified Simulations},
author={Racz, Gabor and Szapudi, Istvan and Dobos, Laszlo and Csabai, Istvan and Szalay, Alexander S.},
year={2018},
month={nov},
archivePrefix={"arXiv"},
primaryClass={astro-ph.CO}
}
We present the multi-GPU realization of the StePS (Stereographically Projected Cosmological Simulations) algorithm with MPI-OpenMP-CUDA hybrid parallelization, and show what parallelization efficiency can be reached. We use a new zoom-in cosmological direct N-body simulation method, that can simulate the infinite universe with unprecedented dynamic range for a given amount of memory and, in contrast to traditional periodic simulations, its fundamental geometry and topology match observations. By using a sperical geometry instead of periodic boundary conditions, and gradually decreasing the mass resolution with radius, our code is capable of running simulations with a few gigaparsecs in diameter and with a mass resolution of ~10^9Ms in the center in four days on three compute nodes with four GTX 1080Ti GPUs each. The code can also be used to run extremely fast simulations with reasonable resolution for fitting cosmological parameters. These simulations can be used for prediction needs of large surveys. The StePS code is publicly available for the research community.
November 18, 2018 by hgpu
