摘要
DRA算法通过建立α队列,动态回收系统空闲时间,利用DVS技术降低系统能耗,但其通常假设处理器提供连续的频率或者电压.为了保证任务的实时性,DRA算法选择的实际运行速度比连续频率情况下计算出的理想速度Sx大,这样会造成系统资源的浪费.本文以DRA算法为基础,针对处理器提供离散频率或电压,提出了DRA-PARTION算法.该算法把任务的执行时间划分为两部分,通过Sx确定第一部分的速度SL和第二部分的速度SH,并且利用理想速度下的执行时间e'x.I计算出第一部分的执行时间e'x.L.待第一部分执行完成,根据剩余执行时间完成第二部分.仿真实验表明DRA-PARTION算法比DRA算法节约大约19.04%的能耗.
DRA algorithm dynamicly recoveries the system idle time by building the a queue and uses DVS technology to reduce sys- tem power consumption ,but it is generally assumed that the processor supports the continuous frequency of voltage levels. In order to guarantee the deadline of real-time task, DRA algorithms select higher speed than the computed ideal speed in the continuous frequen- cy. It will waste the system resources. In this paper,we present a DRA-PARTION algorithm based on DRA algorithm with processors providing the discrete frequency or voltage. The algorithm divides the task~ execution time into two parts. The speed of first part and second part is determined by ideal speed. We can compute the execution time of first part by the execution time with ideal speed. If the first part completed,then completed the second part with the remaining execution time. Simulation results show that DRA-PARTION algorithm provides about 19.04% of energy savings compare to DRA algorithm.
出处
《小型微型计算机系统》
CSCD
北大核心
2014年第3期667-670,共4页
Journal of Chinese Computer Systems
基金
核高基国家科技重大专项项目(2012ZX01029001-002)资助