Abstract
This article presents techniques for reducing idle energy by mode-sequence optimization (MSO) under timing constraints. Our component-level CoMSO algorithm computes energy-optimal mode-transition sequences for different lengths of idle intervals. Our system-level SyMSO algorithm shifts tasks within slack intervals while satisfying all timing and resource constraints in the given schedule. Experimental results on a commercial software-defined radio show that these new techniques can reduce idle energy by 50 - 70%, or 30 - 50% of total system energy over previous offline-optimal but unsequenced techniques based on localized break-even-time analysis, thanks to rich options offered by mode sequencing. © 2007 ACM.