Experiences with OpenMP in tmLQCD
Bartosz Kostrzewa, Albert Deuzeman, Karl Jansen, Carsten Urbach · Proceedings of 31st International Symposium on Lattice Field Theory LATTICE 2013 — PoS(LATTICE 2013) · 2014
An overview is given of the lessons learned from the introduction of multi-threading using OpenMP in tmLQCD.In particular, programming style, performance measurements, cache misses, scaling, thread distribution for hybrid codes, race conditions, the overlapping of communication and computation and the measurement and reduction of certain overheads are discussed.Performance measurements and sampling profiles are given for different implementations of the hopping matrix computational kernel.