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arXiv · 1803.01618

On the accuracy and usefulness of analytic energy models for contemporary multicore processors

Johannes Hofmann·Georg Hager·Dietmar Fey
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Abstract

This paper presents refinements to the execution-cache-memory performance model and a previously published power model for multicore processors. The combination of both enables a very accurate prediction of performance and energy consumption of contemporary multicore processors as a function of relevant parameters such as number of active cores as well as core and Uncore frequencies. Model validation is performed on the Sandy Bridge-EP and Broadwell-EP microarchitectures. Production-related variations in chip quality are demonstrated through a statistical analysis of the fit parameters obtained on one hundred Broadwell-EP CPUs of the same model. Insights from the models are used to explain the performance- and energy-related behavior of the processors for scalable as well as saturating (i.e., memory-bound) codes. In the process we demonstrate the models' capability to identify optimal operating points with respect to highest performance, lowest energy-to-solution, and lowest energy-delay product and identify a set of best practices for energy-efficient execution.

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Johannes Hofmann, Georg Hager, Dietmar Fey. 2018-03-05. On the accuracy and usefulness of analytic energy models for contemporary multicore processors. https://doi.org/10.1007/978-3-319-92040-5_2

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