Quantitative comparison of power management algorithms

Dynamic power management saves power by shutting down idle devices. Several management algorithms have been proposed and demonstrated effective in certain applications. We quantitatively compare the power saving and performance impact of these algorithms on hard disks of a desktop and a notebook computers. This paper has three contributions. First, we build a framework in Windows NT to implement power managers running realistic workloads and directly interacting with users. Second, we define performance degradation that reflects user perception. Finally, we compare power saving and performance of existing algorithms and analyze the difference. 1. Introduction Dynamic power management (DPM) is an effective approach to reduce power consumption without significantly degrading performance 2. DPM shuts down devices when they are not being used and wakes them up when necessary. When a device is not used, it is called idle; otherwise, it is called busy. DPM algorithms observe request patt...