A two-class continuous-time queueing model with dedicated servers and global FCFS service discipline

Abstract

This paper considers a continuous-time queueing model with two types (classes) of customers each having their own dedicated server. The system adopts a "global FCFS" service discipline, i.e., all arriving customers are accommodated in one single FCFS queue, regardless of their types. As a consequence of the "global FCFS" rule, customers of one type may be blocked by customers of the other type, in that they may be unable to reach their dedicated server even at times when this server is idle, i.e., the system is basically non-workconserving. One major aim of the paper is to estimate the negative impact of this phenomenon on the (mean) system occupancy and mean system delay. For this reason, the systems with and without "global FCFS" are studied and compared. The motivation of our work are systems where this kind of blocking is encountered, such as input-queueing network switches or road splits. © 2011 Springer-Verlag.