Skip to content

Re: Speedup issues with OMP


Dear Jepson,rnrn A few years ago we were researching this problem in detail (cf. 2009, Heuveline, V. & Krause, M.J. & Latt, J.: “”Towards a Hybrid Parallelization of Lattice Boltzmann Methods””, article in Computers and Mathematics with Applications, 58, 1071-1080). Basically we found that you need to pin the OMP-threads to specific cores to reach almost the performance obtained using MPI. Unfortunately, you need some system calls to do that. Since we want OpenLB to be as generic as possible, we decided against these optimizations. rnrnIn the mentioned paper you will also find some benchmark results to which you can compare yours. However, for a sufficient large grid size I would expect a better speed-up using 48 cores.rnrnMathias rnrn