PFWRR：能实现比例公平的增强型WRR

PFWRR:An Enhanced WRR Scheduling Realizing the Proportion Fairness Principle

为了实现比例公平原则,在加权轮循调度(WRR)算法的基础上提出了比例公平WRR调度算法——PFWRR.PFWRR依据各队列的平均分组到达率,调整各队列的调度权值,从而在当队列长度小于等于缓冲长度时,保证各队列的平均分组排队时延符合给定比例;当队列长度大于缓冲时,保证各队列的平均分组丢失率符合给定比例.PFWRR的计算负荷是合理的,因为它仅当系统超载且平均分组到达率发生变化时,才调整各队列的服务率.实测性能显示:当系统超载且不出现分组丢失时,PFWRR实现了比例平均分组排队时延保证,当系统出现分组丢失时,PFWRR实现了比例平均分组丢失率保证.

To realize proportion fairness principle, a scheduling based on Weighted Round Robin （WRR） is proposed, whose name is Proportion Fairness WRR（PFWRR）. PFWRR adjusts each queuers weight in terms of the average packet arrival rate to guarantee that the proportion of average queuing delay accords with the differentiation parameters when each queuers length is smaller than or equals to its buffer length and the proportion of average packet loss rate accords with the differentiation parameters when the system begins to drop packets. The computation load of PFWRR is reasonable because it renews each queuers weight only when the system is overloaded and the average packet arrival rate changes. The experiment shows that PFWRR can realize the average queuing delay proportion fairness principle when the system is overloaded but do not drop packets and the average packet loss rate proportion fairness principle when packet loss happens in the system.