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DOE OSTI · 1286913

A new deadlock resolution protocol and message matching algorithm for the extreme-scale simulator

Engelmann, Christian·Naughton, III, Thomas J.
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Abstract

Investigating the performance of parallel applications at scale on future high-performance computing (HPC) architectures and the performance impact of different HPC architecture choices is an important component of HPC hardware/software co-design. The Extreme-scale Simulator (xSim) is a simulation 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 overhead and (2)~a new simulated MPI message matching algorithm to reduce the oversubscription management overhead. The results clearly show a significant performance improvement. The simulation overhead for running the NAS Parallel Benchmark suite was reduced from 102% to 0% for the embarrassingly parallel (EP) benchmark and from 1,020% to 238% for the conjugate gradient (CG) benchmark. xSim offers a highly accurate simulation mode for better tracking of injected MPI process failures. Furthermore, with highly accurate simulation, the overhead was reduced from 3,332% to 204% for EP and from 37,511% to 13,808% for CG.

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97 MATHEMATICS AND COMPUTINGhigh-performance computingmessage passing interfaceparallel discrete event simulationperformance prediction

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Engelmann, Christian, Naughton, III, Thomas J.. 2016-03-22. A new deadlock resolution protocol and message matching algorithm for the extreme-scale simulator. https://doi.org/10.1002/cpe.3805

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