Task-Based Parallelism with OpenMP: a case study with DL_POLY_4

ABSTRACT

When performing computations where load balancing is complex, dynamic load balancing is becoming increasingly necessary. In this paper, we examine one of these methods, Task-Based Parallelism. Many libraries implement Task-Based Parallelism, however, in this paper we examine the OpenMP standard and implementations, and apply it to the Classical Molecular Dynamics code, DL_POLY_4, focusing on the two body force calculations that make up a large percentage of the compute in many simulation runs. Our results show reasonable performance using OpenMP tasks, however, some of the extensions available in other libraries such as OmpSs or StarPU may help with performance for problems similar to Molecular Dynamics, where avoiding race conditions between tasks can have a substantial scheduling overhead.

KEYWORDS:

• DL_POLY_4
• OpenMP
• task parallelism
• molecular dynamics

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 http://www.ks.uiuc.edu/Research/gpu/files/ICMS-Edinburgh/ShortRangeNAMD.pdf.