A User-Customizable Energy-Adaptive Combined Static/Dynamic Scheduler for Mobile Applications

In mobile applications, the energy consumed by OS and application tasks primarily comes from limited DC battery source, which imposes an upper bound to the amount of time available for execution of tasks. To achieve the best Energy-aware Quality-of-Service (EQoS), it is important to prioritize the scheduling of critical tasks over non-critical tasks to improve overall performance while extending the battery life. Using the Combined Static/Dynamic scheduler (CSD) in the EMERALDS operating system [9, 10] as a basis, we developed the Energy-Adaptive CSD (EA-CSD) with an energy-aware scheduling algorithm1 that executes tasks to achieve effective use of limited energy by favoring low-energy and critical tasks. Our simulation of the EA-CSD shows that battery life can be extended up to about 100% with varying degrees of performance degradation of up to about 40%, and the actual values of both are fully customizable by the user through parametric adjustment.