Title
A Queue-Length Cutoff Model for a Preemptive Two-Priority $M/M/1$ System
Abstract
We consider a two-priority, preemptive, single-server queueing model. Each customer is classified into either a high-priority class or a low-priority class. The arrivals of the two-priority classes follow independent Poisson processes, and service time is assumed to be exponentially distributed. A queue-length cutoff method is considered. Under this discipline the server responds only to high-priority customers until the queue length of the other class exceeds a threshold L. After that the server switches to handle only the low-priority queue. Steady-state balance equations are established for this system. Then we introduce two-dimensional generating functions to obtain the average number of customers for each priority class. We then focus on the preemptive resume case while allowing for weights associated with both priority class queues. We develop methodologies to obtain the optimal cutoffs for the situation when the weights of both queues are constant (i.e., not a function of queue length) and the situation when the weights change linearly with the queue lengths. It is important to point out that our method does not lead to a closed-form exact solution, but rather to a numerical approximation, from which cutoff policies are analyzed.
Year
DOI
Venue
2006
10.1137/050648146
SIAM JOURNAL ON APPLIED MATHEMATICS
Keywords
Field
DocType
priority queue,queue-length cutoff,generating function
M/M/1 queue,M/D/1 queue,Mathematical optimization,Bulk queue,M/M/c queue,M/G/1 queue,M/G/k queue,M/D/c queue,Priority queue,Mathematics
Journal
Volume
Issue
ISSN
67
1
0036-1399
Citations 
PageRank 
References 
8
0.56
3
Authors
2
Name
Order
Citations
PageRank
Qiang Gong1493.23
Rajan Batta284989.39