Achieving High Parallel Efficiency on Modern Processors for X-Ray Scattering Data Analysis.

Modern processors have increasingly more parallelism available on-chip, which include simultaneous multithreading (SMT) and single-instruction multiple-data (SIMD) parallelisms. The former is typically available through multiple compute cores and the latter through long vector units. In this paper, we consider several compute kernels of a real-world scientific application, X-ray scattering data analysis, to demonstrate and analyze high performance through the exploitation of available SMT and SIMD parallelism on such modern processors, which form the base of current state-of-the-art supercomputers. We discuss various methods to effectively exploit the available on-node parallelism to increase parallel efficiency and provide detailed performance analysis on two leading Cray supercomputers. In addition, we also present performance results obtained on the Intel Knights Landing processor.