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arXiv · 1104.4874

LIKWID: Lightweight Performance Tools

Jan Treibig·Georg Hager·Gerhard Wellein
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Abstract

Exploiting the performance of today's microprocessors requires intimate knowledge of the microarchitecture as well as an awareness of the ever-growing complexity in thread and cache topology. LIKWID is a set of command line utilities that addresses four key problems: Probing the thread and cache topology of a shared-memory node, enforcing thread-core affinity on a program, measuring performance counter metrics, and microbenchmarking for reliable upper performance bounds. Moreover, it includes a mpirun wrapper allowing for portable thread-core affinity in MPI and hybrid MPI/threaded applications. To demonstrate the capabilities of the tool set we show the influence of thread affinity on performance using the well-known OpenMP STREAM triad benchmark, use hardware counter tools to study the performance of a stencil code, and finally show how to detect bandwidth problems on ccNUMA-based compute nodes.

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Jan Treibig, Georg Hager, Gerhard Wellein. 2013-01-07. LIKWID: Lightweight Performance Tools. https://doi.org/10.1109/icppw.2010.38

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