一种新的静态优先级在线节能调度算法

A new energy-efficient online scheduling algorithm for static priority real-time systems

合理运用动态电压调整技术可有效降低嵌入式实时系统能耗.针对静态优先级实时调度,提出了一种能够有效分析松弛时间并尽可能平衡分配松弛时间的在线节能调度算法TPSRM.设计了一种两段式频率执行策略来改变任务执行时间的分配,能充分在线分析各种形式的松弛时间.通过尽可能合理降低高优先级任务的处理器执行频率来实现有效的在线频率调整.实验结果表明TPSRM算法可实现较好的节能效果.

Power is a valuable resource in embedded real-time systems as the lifetime of many such systems is constrained by their battery capacity. Recent advances in processor design have added support for dynamic frequency/voltage scaling for saving power and energy. Static priority scheduling algorithms is widely used in real-time systems and energy-efficient scheduling algorithms for static priority real-time systems are urgently needed to be designed. The limitations of energy-efficient scheduling were discussed and a new energy-efficient voltage scaling algorithm was proposed based on the rate monotonic algorithms. The algorithm can analyze slack time more effectively and try to balance the distribution of slack time among tasks of different priorities. A two-phase frequency scaling strategy was designed in order to change the execution time of real-time tasks. The proposed algorithm tried to lower the frequency of real-time tasks of higher priority by analyzing all the slack times. Experimental results demonstrate that this algorithm can save up to 26.2% more energy than the DPM algorithm.