Improving the Performance of the Extreme-scale Simulator
By:
Engelmann, Christian ; Naughton III, Thomas J
Page Number:
198-207
Book Title:
Proceedings of the 18th IEEE/ACM International Symposium on Distributed Simulation and Real Time Applications (DS-RT) 2014
Publication Date:
December 2014
Publisher Location:
IEEE Computer Society
Conference Name:
18th IEEE/ACM International Symposium on Distributed Simulation and Real Time Applications (DS-RT) 2014
Conference Location:
Toulouse, France
Abstract
Investigating the performance of parallel applications at scale on future high-performance computing (HPC) architectures and the performance impact of different architecture choices is an important component of HPC hardware/software co-design. The Extreme-scale Simulator (xSim) is a simulation-based toolkit for investigating the performance of parallel applications at scale. xSim scales to millions of simulated Message Passing Interface (MPI) processes. The overhead introduced by a simulation tool is an important performance and productivity aspect. This paper documents two improvements to xSim: (1) a new deadlock resolution protocol to reduce the parallel discrete event simulation management overhead and (2) a new simulated MPI message matching algorithm to reduce the oversubscription management overhead. The results clearly show a significant performance improvement, such as by reducing the simulation overhead for running the NAS Parallel Benchmark suite inside the simulator from 1,020% to 238% for the conjugate gradient (CG) benchmark and from 102% to 0% for the embarrassingly parallel (EP) and benchmark, as well as, from 37,511% to 13,808% for CG and from 3,332% to 204% for EP with accurate process failure simulation.
