A power metric for mobile systems

The advent of mobile computing has made power consumption a critical design factor. There has been little systematic consideration of the power sources for mobile computing systems. This paper presents a class of system-level metrics intended to make a systematic study more feasible and to more accurately reflect the trade-off between battery life and performance. An example involving the clock frequency of a CPU shows the possible impact of the nonlinearity, an impact not predicted by existing metrics. Results of an initial attempt to verify the example are presented and explained. The paper concludes with drawbacks of the metric and possible extensions to overcome these drawbacks.