Making applications faster by asynchronous execution: Slowing down processes or relaxing MPI collectives

Afzal A, Hager G, Markidis S, Wellein G (2023)

Publication Language: English

Publication Type: Journal article

Publication year: 2023

Journal

Future Generation Computer Systems-The International Journal of Grid Computing Theory Methods and Applications Elsevier

DOI: 10.1016/j.future.2023.06.017

Abstract

Comprehending the performance bottlenecks at the core of the intricate hardware-software interactions exhibited by highly parallel programs on HPC clusters is crucial. This paper sheds light on the issue of automatically asynchronous MPI communication in memory-bound parallel programs on multicore clusters and how it can be facilitated. For instance, slowing down MPI processes by deliberate injection of delays can improve performance if certain conditions are met. This leads to the counter-intuitive conclusion that noise, independent of its source, is not always detrimental but can be leveraged for performance improvements. We employ phase-space graphs as a new tool to visualize parallel program dynamics. They are useful in spotting certain patterns in parallel execution that will easily go unnoticed with traditional tracing tools. We investigate five different microbenchmarks and applications on different supercomputer platforms: an MPI-augmented STREAM Triad, two implementations of Lattice-Boltzmann fluid solvers (D3Q19 and SPEChpc D2Q37), the LULESH and HPCG proxy applications.

Authors with CRIS profile

Ayesha Afzal Regionales Rechenzentrum Erlangen (RRZE) Georg Hager Regionales Rechenzentrum Erlangen (RRZE) Gerhard Wellein Professur für Höchstleistungsrechnen

Additional Organisation(s)

FAU Profilzentrum Licht.Materie.Quantentechnologien (FAU LMQ) Erlangen National High Performance Computing Center (NHR@FAU)

Involved external institutions

Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH) SE Sweden (SE)

How to cite

APA:

Afzal, A., Hager, G., Markidis, S., & Wellein, G. (2023). Making applications faster by asynchronous execution: Slowing down processes or relaxing MPI collectives. Future Generation Computer Systems-The International Journal of Grid Computing Theory Methods and Applications. https://doi.org/10.1016/j.future.2023.06.017

MLA:

Afzal, Ayesha, et al. "Making applications faster by asynchronous execution: Slowing down processes or relaxing MPI collectives." Future Generation Computer Systems-The International Journal of Grid Computing Theory Methods and Applications (2023).

BibTeX: Download