共享存储器交换的排队模型

Queueing analysis of shared-memory switch

对于共享存储器交换结构,传统的排队模型的分析基于时隙,只能给出总的丢包性能,不能准确给出在不平衡业务分布下,不同的输入端口所具有的不同丢包性能。文中提出共享存储器交换结构在任意输出分布下的一种排队模型,对于完全共享(CS)以及具有最大队长限制的共享(SMXQ)两种存储器共享策略进行了性能分析。该模型基于子时隙建立多个状态空间和相邻子时隙之间的概率转移矩阵。通过仿真验证了所提出的排队模型的准确性。

This paper presents a queueing model of a shared-memory switch with an arbitrary output distribution and analyzes the performance of two memory sharing schemes: complete sharing (CS) and sharing with maximum queue (SMXQ). Traditional models based on timeslots give only approximate results and can not show the unfair serving among input ports with non-uniform traffic distribution. The new queueing model based on sub-timeslots reveals precise performance results among input ports. The results have been validated by simulation.