Characterizing the use of DVFS for HPC I/O optimization: A Microbenchmarking Approach

The scale of HPC clusters has increased over the past decade, eventually achieving exascale in 2022. While the shift to exascale computing meets the rising demand for processing power, it introduces challenges in energy consumption and power efficiency. Dynamic Voltage and Frequency Scaling (DVFS), is a common tool that can be used to reduce the processor's power usage. However, while the effect of DVFS during classical compute tasks has already been well-documented, its impact on I/Os has not been covered by the literature. In this paper, we offer a comprehensive investigation of the impact of DVFS on a compute node comprising two AMD EPYC Rome 7282 CPU in an HPC cluster. Our contributions include (1) a methodology to microbenchmark the performance and energy consumption impact of DVFS in an HPC system through the use of carefully selected synthetic application, (2) a set of results and analysis related to the behavior of DVFS on the tested HPC nodes, and (3) some guidelines for using DVFS on HPC applications.