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Some comparability results for waiting times in single- and many-server queues

Published online by Cambridge University Press:  14 July 2016

D. J. Daley*
Affiliation:
The Australian National University
T. Rolski*
Affiliation:
Wrocław University
*
Postal address: Statistics Department, IAS, The Australian National University, GPO Box 4, Canberra ACT 2601, Australia.
∗∗Postal address: Mathematics Institute, Wrocław University, pl. Grunwaldski 2/4, 50-384 Wrocław, Poland.

Abstract

It is shown that the stationary waiting time random variables W′, W″ of two M/G/l queueing systems for which the corresponding service time random variables satisfy E(Sx)+E(Sx)+ (all x >0), are stochastically ordered as WdW. The weaker conclusion, that E(Wx)+E(Wx)+ (all x > 0), is shown to hold in GI/M/k systems when the interarrival time random variables satisfy E(xT)+E(xT)+ (all x). A sufficient condition for wkEW in GI/D/k to be monotonic in k for a sequence of k-server queues with the same relative traffic intensity is given. Evidence indicating or refuting possible strengthenings of some of the results is indicated.

Type
Research Papers
Copyright
Copyright © Applied Probability Trust 1984 

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Footnotes

Work done during the tenure of a Visiting Fellowship at The Australian National University.

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