WPC: Whole-Picture Workload Characterization Across Intermediate Representation, ISA, and Microarchitecture

This letter reveals that performing microarchitecture-dependent, or microarchitecture-independent, or ISA-independent workload characterization alone will lead to misleading or even erroneous conclusions. We present a whole-picture workload characterization (in short, WPC) methodology and the tool. WPC integrates microarchitecture-dependent, microarchitecture-independent, and ISA-independent characterization methodologies. It performs a whole-picture analysis on hierarchical profile data across Intermediate Representation (IR), ISA, and microarchitecture to sum up the inherent workload characteristics and understand the reasons behind the numbers. We contradict an influential observation using the WPC tool: having higher front-end stalls is an intrinsic characteristic of scale-out workloads. Our experiments show collecting microarchitecture metrics at only one level without understanding the reason behind the numbers might lead to erroneous conclusions. We open-source the WPC tool from the project homepage
https://www.benchcouncil.org/WPC
.