FPowerTool: A function-level power profiling tool

This paper presents the design and implementation of FPowerTool, a lightweight function-level profiling tool for measuring the energy consumption of program code. Based on the trace of energy usage and the timestamps of programs execution events, FPowerTool monitors and analyzes the power consumption of a program at runtime. Two issues have been addressed: associating the power consumption data with the individual function code segments and reducing the overhead of power profiling. FPowerTool adopts an approach which takes advantage of both sampling and dynamic instrumentation to address those issues. The energy consumed by code at the granularity of function is measured by sampling the energy usage hardware counters built in the CPU and the sampled value is associated to the corresponding code segments by offline analysis. Experiment results show that this approach significantly reduces the overhead of the program power profiling without significant interference to the timing of the original program execution.