Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-27T10:41:58.395Z Has data issue: false hasContentIssue false

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 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

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

References

Daley, D. J. (1983) Some results for the mean waiting-time and work-load in GI/G/k queues.Google Scholar
Kiefer, J. and Wolfowitz, J. (1955) On the theory of queues with many servers. Trans. Amer. Math. Soc. 78, 118.CrossRefGoogle Scholar
Makino, T. (1969) Investigation of the mean waiting time for queueing systems with many servers. Ann. Inst. Statist. Math. 21, 357366.Google Scholar
Mori, M. (1975) Some bounds for queues. J. Operat. Res. Soc. Japan. 18, 152181.Google Scholar
Rolski, T. and Stoyan, D. (1976) On the comparison of waiting times in GI/G/1 queues. Operat. Res. 24, 197200.Google Scholar
Ross, S. ?. (1978) Average delay in queues with non-stationary Poisson arrivals. J. Appl. Prob. 15, 602609.CrossRefGoogle Scholar
Stoyan, D. (1983) Comparison Methods for Queues and Other Stochastic Models, John Wiley, Chichester. (English translation and revision, ed. Daley, D. J., of Qualitativ Eigenschaften und Abschatzungen der Stochastischer Modelle (1977), Akademie-Verlag, Berlin.) Google Scholar
Stoyan, D. and Stoyan, H. (1969) Monotonieeigenschaften der Kundenwartezeiten im Modell GI/G/1. Z. angew. Math. Mech. 49, 729734.CrossRefGoogle Scholar
Stoyan, D. and Stoyan, H. (1974) Inequalities for the mean waiting time in single-line queueing systems (in Russian). Izv. Akad. Nauk. SSSR Tehn. Kibernet. 1974: 6, 104106 (= Engng. Cybernetics 12(6), 79–81).Google Scholar
Whitt, W. (1983) Comparison conjectures about the M/G/s queue. Operat. Res. Letters 2, 203209.Google Scholar
Whitt, W. (1984) Minimizing delays in the GI/G/1 queue. Operat. Res. 32, 4151.Google Scholar
Wolff, R. W. (1977) The effect of service time regularity on system performance. In Computer Performance, ed. Chandy, K. M. and Reiser, M., North-Holland, Amsterdam, 297304.Google Scholar