Currentcy: a unifying abstraction for expressing energy management policies

• Authors: Heng Zeng;Carla S. Ellis;Alvin R. Lebeck;Amin Vahdat
• Venue: ATEC '03 Proceedings of the annual conference on USENIX Annual Technical Conference
• Year: 2003

The global nature of energy creates challenges and opportunities for developing operating system policies to effectively manage energy consumption in battery-powered mobile/wireless devices. The proposed currentcy model creates the framework for the operating system to manage energy as a first-class resource. Furthermore, currentcy provides a powerful mechanism to formulate energy goals and to unify resource management policies across diverse competing applications and spanning device components with very different power characteristics. This paper explores the ability of the currentcy model to capture more complex interactions and to express more mature energy goals than previously considered. We carry out this exploration in ECOSystem, an "energy-centric" Linux-based operating system. We extend ECOSystem to address four new goals: 1) reducing residual battery capacity at the end of the targeted battery lifetime when it is no longer required (e.g., recharging is available), 2) dynamic tracking of the energy needs of competing applications for more effective energy sharing, 3) reducing response time variation caused by limited energy availability, and 4) energy efficient disk management. Our results show that the currentcy model can express complex energy-related goals and behaviors, leading to more effective, unified management policies than those that develop from per-device approaches.