基于时延的动态优先级调度算法

Delay-Based Dynamic Priority Queue Scheduling

队列管理是提高网络QoS的一种有效方法。在基于时延的调度算法(BDS)基础上将时间片与优先级相结合,提出了一种基于时延的动态优先级调度算法(DDPQS)。为了实现该算法,针对进入缓冲区的每个子队列设置一个计数器,以调整的计数器值为基准来动态的改变队列的优先级,从而达到队列调度的效果;又从研究该算法的过程中,发现其局限性,即计数器值对时间片过于敏感的问题,于是进一步采用设置阈值进行区分的方法来优化。优化前后的仿真结果表明,时延和吞吐率性能具有明显改善。

Queue management is an effective method to improve the QoS of network.Investigating queue management based on the delay scheduling（BDS）,combining the time chip and priority,advances Delay-based Dynamic Priority Queue Scheduling（DDPQS） algorithm.To achieve the algorithm,sets a counter for every sub-queue entering the buffer.It dynamically adjusts the sub-queue priorities by the value of counters to achieve the effect of queue scheduling.During the research,the limitation was found that the counters are sensitive to the time chip.The paper uses threshold values to optimize the algorithm.The simulation results before and after the optimizations demonstrate that the performance of the delay and the throughput rate has significantly improved.