摘要
调度算法对操作系统中的实时性起着关键的作用。就此问题,深入分析了基于最小优裕度算法的内核进程调度算法,为更好地满足Linux系统对嵌入式系统实时可靠性的要求,对现有的LSF调度策略进行分析,指出LSF算法调度算法的不足。为了改进LSF算法的颠簸现象,基于抢占阈值的思想,提出适用于LSF算法的抢占阈值分配方法,动态地给每个任务配置抢占阈值,以此提高了Linux系统的实时性及吞吐量。经过实验证明,通过对LSF算法的改进,任务之间的切换大大减少,同时也未对系统造成大的开销.
Scheduling algorithm plays the vital role in operating system. Contacting the characteristics of the LSF （least slack first） kernel process schedule algorithm is analyzed in depth.In order to meet the requirement of real—time and reliable characteristic to the Linux system,the existent schedule is analyzed.The shortage of LSF schedule algorithm is pointed out. In order to relieve the thrashing caused by LSF,some applicable assigning schemes are presented to the LSF algorithm based on the preemption threshold , every task is dynamically assigned a preemption threshold that is dynamically changed. Such method of scheduling is bought forward to improve the real time characteristic and throughput of the Linux.Experiment show that, by using the improved LSF policy, the switching among tasks decreases greatly while the cost of system resource are really low.
出处
《电子测试》
2011年第3期71-75,共5页
Electronic Test
关键词
机顶盒
实时
进程调度
最小裕度算法
STB（set top box）
real-time
process schedule
LSF（least slack first）
