嵌入式系统节能调度的空闲时间利用策略

Slack Utilization Strategy in Energy Saving Task Scheduling for Embedded Systems

针对现有算法不能在保证调度有效的前提下实现满意节能效果的问题,分析了空闲时间与动态电压升降的关系,提出了统筹可用空闲时间的策略和逆向的电流-空闲时间优先(CSFB)的节能调度算法,并进行了仿真与对比.结果表明,统筹策略普遍适用于嵌入式系统的节能调度;对于典型高功耗任务集,CSFB算法的电量保有率和空闲时间利用率相比同类有效算法分别提高了12.29%和37.03%,能有效延长嵌入式系统的工作时间,实现更佳节能效果.

While utilizing slack to scale down system voltage/speed and therefore save energy has been widely accepted, its strategy has not been systematically discussed yet. In this paper, we compared and analyzed various previous approaches, proposed OPS （overall planning）, the slack utilization strategy and CSFB （current-slack first-backwards） algorithm, and analyzed their performance through simulation. Resuits indicate that our strategy is capable to schedule task sets of all loads efficiently, and our algorithm achieves 37.03% higher slack utilization ratio and 12.29% higher remaining charge ratio on average than other successful algorithms in scheduling typical heavy-loaded tasks.