A new sustained system performance metric for scientific performance evaluation

Because of the increasing complexities of systems and applications, the performance of many traditional HPC benchmarks, such as HPL or HPCG, no longer correlates strongly with the actual performance of real applications. To address the discrepancy between simple benchmarks and real applications, and to better understand the application performance of systems, some metrics use a set of either real applications or mini applications. In particular, the Sustained System Performance (SSP) metric Kramer et al. (The NERSC sustained system performance (SSP) metric. Tech Rep LBNL-58868, 2005), which indicates the expected throughput of different applications executing with different datasets, is widely used. Whereas such a metric should lead to direct insights on the actual performance of real applications, sometimes more effort is necessary to port and evaluate complex applications. In this study, to obtain the approximate performance of SSP representing real applications, without running real applications, we propose a metric called the Simplified Sustained System Performance (SSSP) metric, which is computed based on several benchmark scores and their respective weighting factors, and we construct a method evaluating the SSSP metric of a system. The weighting factors are obtained by minimizing the gap between the SSP and SSSP scores based on a small set of reference systems. We evaluated the applicability of the SSSP method using eight systems and demonstrated that our proposed SSSP metrics produce appropriate performance projections of the SSP metrics of these systems, even when we adopted a simple method for computing the weighting factors. Additionally, the robustness of our SSSP metric was confirmed via computation of the weighting factors based on a smaller set of reference systems and computation of the SSSP metrics of other systems.