A scalable algorithm for many-body dissipative particle dynamics using multiple general purpose graphic processing units

We present a novel algorithm for the many-body Dissipative Particle Dynamics (DPD) forces calculation which allows to efficiently scale the DL_MESO software package on Multiple General Purpose Graphic Processing Units. Together with the extension to 64-bit integer arrays and addition of hard surface boundary conditions, the proposed algorithm allows to simulate very large complex mesoscale systems up to 14 billion beads. The implementation takes advantages of the CUDA language stream features to overlap the exchange of particle positions and local densities and the computation of the short range forces. We tested a water drop between two plates system using tree of the main European supercomputers: Piz Daint, Marconi and JUWELS. Results shows an improvement on the speedup compared to a naive implementation up to 1.5x when using 1024 GPUs.