【摘要】 提出基于任务同步及节能的动态实时调度算法HDSA(hybrid dynamic scheduling algorithm),以有效地解决任务同步及节能的难题。HDSA结合RM及EDF算法,在满足任务实时可调度性及任务同步的限制条件下,采用DVFS节省能耗。HDSA包含静态算法及动态算法两部分。静态算法在静态条件下,求出任务的静态速度。动态调度算法在实际运行中,固定临界区的运行速度,并充分回收、利用任务运行时的空闲执行时间,调节处理器的速度,以有效降低能耗并满足实时可调度性。同时避免高优先权任务被阻塞时,临界区继承高优先权任务的速度时所造成的处理器电压开关的频繁切换,因而能有效地降低实时任务调度的成本。实验测试表明,HDSA在调度性能上明显优于目前所知的有效算法。更多还原

【Abstract】 HDSA(hybrid dynamic scheduling algorithm) was proposeed,which slows down processor via voltage/frequency scaling,such that the real-time schedulability and task synchronization can be satisfied concurrently with as minimum as possible energy consumption.Based on RM and EDF,HDSA consists of a static algorithm and a dynamic one.The static algorithm computes the initially static speeds of all tasks under the static conditions.The dynamic algorithm fixes the execution frequencies of all critical sections at runtime,and reclaims the slack of tasks during their executions so as to further reduce energy consumption while satisfying timing constraints.On the other hand,frequent voltage switching,which is caused by the frequency inheritance,can be avoided by the approach when a task with a lower priority blocks a task with a higher priority.Consequently,the scheduling costs can also be reduced efficiently.The experimental results illustrate that the proposed algorithm obviously outperforms existing algorithms in terms of energy consumption.更多还原