—Energy consumption continues to be a major concern in multiple application domains including powerhungry data centers, portable and wearable devices, mobile communication devices and wireless sensor networks. While energy-constrained, many such applications must meet timing and QoS constraints for sensing, actuation or multimedia data processing. Many modern power-aware processors and microcontrollers have built-in support for active, idle and sleep operating modes. In sleep mode, substantially more energy savings can be obtained but it requires a significant amount of time to switch into and out of that mode. Hence, a significant amount of energy is lost due to idle gaps between executing tasks that are shorter than the required time for the processor to enter the sleep mode. We present a technique called RateHarmonized Scheduling that naturally clusters task execution such that processor idle times are lumped together. We next introduce the Energy-Saving Rate-Harmonized Schedule...