High-order Method for a New Generation of Large Eddy Simulation Solver

Adrien Cassagne (1) , Jean-François Boussuge (2) , Guillaume Puigt (2)

1 CINES - Centre Informatique National de l'Enseignement Supérieur
2 CERFACS - Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique

We enabled hybrid OpenMP/MPI computations for a new generation of CFD code based on a new high-order method (Spectral Difference method) dedicated to Large Eddy Simulation (LES). The code is written in Fortran 90 with MPI library and OpenMP directives for the parallelization. This white-paper is focused on achieving good performances with the OpenMP shared memory model on standard environment (bi-socket nodes and multi-core x86 processors). The goal was to reduce the number of MPI communications by considering MPI communications between nodes and OpenMP approach for all cores on any node. Three different approaches are compared: full MPI, full OpenMP and hybrid OpenMP/MPI. We observed that hybrid and full MPI computations took nearly the same time for a small number of cores.

Domaines: Calcul parallèle, distribué et partagé [cs.DC]; Mécanique des fluides [physics.class-ph]

Adrien Cassagne, Jean-François Boussuge, Guillaume Puigt. High-order Method for a New Generation of Large Eddy Simulation Solver. [Technical Report] PRACE. 2015. ⟨hal-01965638⟩