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Stochastic comparisons for fork-join queues with exponential processing times

Published online by Cambridge University Press:  14 July 2016

Esther Frostig*
Affiliation:
Haifa University
Tapani Lehtonen*
Affiliation:
Helsinki School of Economics
*
Postal address: Department of Statistics, Haifa University, Haifa, Israel, 31905.
∗∗Postal address: Helsinki School of Economics, Runebergink 14-16, 00100 Helsinki, Finland.

Abstract

Consider a fork-join queue, where each job upon arrival splits into k tasks and each joins a separate queue that is attended by a single server. Service times are independent, exponentially distributed random variables. Server i works at rate , where μ is constant. We prove that the departure process becomes stochastically faster as the service rates become more homogeneous in the sense of stochastic majorization. Consequently, when all k servers work with equal rates the departure process is stochastically maximized.

MSC classification

Type
Research Article
Copyright
Copyright © Applied Probability Trust 1997 

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