Comparing Algorithms for Dynamic Speed-Setting of a Low-Power CPU

TitleComparing Algorithms for Dynamic Speed-Setting of a Low-Power CPU
Publication TypeTechnical Report
Year of Publication1995
AuthorsGovil, K., Chan E., & Wasserman H.
Other Numbers957
Keywordsportable, power usage, ubiquitous, variable-speed CPU

To take advantage of the full potential of ubiquitous computing devices, we will need systems which minimize power consumption. Weiser et al. and others have suggested that this may be accomplished in part by a CPU which dynamically changes speed and voltage, thereby saving energy by spreading run cycles into idle time. Here we continue this research, using a simulation to compare a number of policies for dynamic speed-setting. Our work clarifies a fundamental power vs. delay tradeoff, as well as the role of prediction and of speed-smoothing in dynamic speed-setting policies. We conclude that success seems to depend more on simple smoothing algorithms than on sophisticated prediction techniques, but defer to the eventual replication of these results on actual multiple-speed systems.

Bibliographic Notes

ICSI Technical Report TR-95-017

Abbreviated Authors

K. Govil, E. Chan, and H. Wasserman

ICSI Publication Type

Technical Report