AutoDVS: An Automatic, General-Purpose, Dynamic Clock Scheduling System for Hand-Held Devices

We present AutoDVS, a dynamic voltage scaling (DVS) system for theHP iPAQ hand-held computer. AutoDVS unifies existing DVStechniques into a single system that significantly reducesthe power consumption of popular, general-purpose, iPAQ software. Moreover, it does so without degrading the user\'s experience perceivably. AutoDVS automatically infers periodsof user interactivity and non-interactivity and applies different DVS policies to each period type. We have implemented AutoDVSas a freely-available, kernel-patch for Familiar Linux and the iPAQ Opie Window Manager. We evaluated AutoDVS using real user workloads of iPAQ software running alone and concurrently. AutoDVS decreasesenergy consumption by 30-70% for interactive programs, by up to 19% for soft real-time applications, and by 12% when these different programtypes run concurrently.