为了解决现有多核实时调度算法要么利用率界限低、要么开销大的问题,在k分组的半局部最早时限优先算法的基础上提出了一个轻量的多核实时调度算法PSEKG.该算法引入一种周期敏感的机制,在任务分配之前先将周期成倍数关系的任务组织在一起,然后将短周期任务和长周期任务分别组织,最后将这些组织好的任务分配到处理器上.实验结果表明:本文提出的方法极大地减少了算法的调度次数、任务的切换次数和任务的迁移次数,实现了降低调度开销的目的.
In order to solve the problem of the existing multicore real-time scheduling algorithms either having low utilization or having high overhead, a lightweight multicore real-time scheduling algorithm PSEKG, based on the EKG algorithm, was proposed. A period-sensitive mechanism was introduced into this algorithm. First, it organized the tasks into sets in which the period of task ti was integer times of that of ti-1 (1 〈 i 〈 n). Then, it separately organized small period tasks and big period tasks into sets. At last, it allocated these tasks to processors set by set. Our experiment results showed that the newly proposed method greatly reduced the number of scheduling times, context switches and task migrations, thus reducing the scheduling overhead.