Frequency–Voltage Cooperative CPU Power Control: A Design Rule and Its Application by Feedback Prediction

Frequency–voltage cooperative power control (FVC) is a powerful method to reduce the CPU power consump-tion of a program during execution, because it utilizes the information on the software workload dynamically. In this paper, we first show through a mathematical analysis the design rule to determine the necessary frequencies and its effect. Then we show experimental results of implementing an FVC with a feedback algorithm on MPEG-4 video and MP3 audio decoders with two sets of frequency and volt-age. The FVC gave a 72 % reduction in CPU power con-sumption during execution. In addition, we show a “Cool-Start ” method that begins the FVC at a lower fre-quency and improves the power reduction effect. © 2005 Wiley Periodicals, Inc. Syst Comp Jpn, 36(6): 39–48, 2005