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On the heavy-traffic limit theorem for GI/G/∞ queues

Published online by Cambridge University Press:  01 July 2016

Ward Whitt*
Affiliation:
Bell Laboratories
*
Postal address: WB-1A350, Bell Laboratories, Holmdel, NJ 07733, U.S.A.

Abstract

A revealing alternate proof is provided for the Iglehart (1965), (1973)–Borovkov (1967) heavy-traffic limit theorem for GI/G/s queues. This kind of heavy traffic is obtained by considering a sequence of GI/G/s systems with the numbers of servers and the arrival rates going to ∞ while the service-time distributions are held fixed. The theorem establishes convergence to a Gaussian process, which in general is not Markov, for an appropriate normalization of the sequence of stochastic processes representing the number of customers in service at arbitrary times. The key idea in the new proof is to consider service-time distributions that are randomly stopped sums of exponential phases, and then work with the discrete-time vector-valued Markov chain representing the number of customers in each phase of service at arrival epochs. It is then easy to show that this sequence of Markov chains converges to a multivariate O–U (Ornstein–Uhlenbeck) diffusion process by applying simple criteria in Stroock and Varadhan (1979). The Iglehart–Borovkov limit for these special service-time distributions is the sum of the components of this multivariate O–U process. Heavy-traffic convergence is also established for the steady-state distributions of GI/M/s queues under the same conditions by exploiting stochastic-order properties.

Type
Research Article
Copyright
Copyright © Applied Probability Trust 1982 

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References

Arnold, L. (1974) Stochastic Differential Equations: Theory and Applications. Wiley, New York.Google Scholar
Beekman, J. A. (1974) Two Stochastic Processes. Almqvist and Wiksell, Stockholm.Google Scholar
Billingsley, P. (1968) Convergence of Probability Measures. Wiley, New York.Google Scholar
Borovkov, A. A. (1967) On limit laws for service processes in multi-channel systems. Siberian Math. J. 8, 746763.CrossRefGoogle Scholar
Borovkov, A. A. (1976) Stochastic Processes in Queueing Theory. Springer-Verlag, New York.Google Scholar
Breiman, L. (1968) Probability. Addison-Wesley, Reading, Ma.Google Scholar
Brillinger, D. R. (1974) Cross-spectral analysis of processes with stationary increments including the stationary GI/G/∞ queue. Ann. Prob. 2, 815827.CrossRefGoogle Scholar
De Smit, J. H. A. (1973a) Some general results for many server queues. Adv. Appl. Prob. 5, 153169.Google Scholar
De Smit, J. H. A. (1973b) On the many server queue with exponential service times. Adv. Appl. Prob. 5, 170182.CrossRefGoogle Scholar
Doob, J. L. (1953) Stochastic Processes. Wiley, New York.Google Scholar
Finkbeiner, D. T. (1966) Introduction to Matrices and Linear Transformations, 2nd edn. W. H. Freeman, San Francisco.Google Scholar
Franken, P. (1975) Stationary probabilities of states of queueing systems at different times. Engineering Cybernetics 1, 8489.Google Scholar
Franken, P. (1976a) Some applications of point processes in queueing theory, I (in German). Math. Nachr. 70, 303319.Google Scholar
Franken, P. (1976b) On the investigation of queueing and reliability models with the help of point processes. Department of Mathematics, Humboldt University, Berlin, DDR.Google Scholar
Franken, P., König, D., Arndt, U. and Schmidt, V. (1981) Queues and Point Processes. Akademie-Verlag, Berlin.Google Scholar
Gikhman, I. I. and Skorohod, A. V. (1969) Introduction to the Theory of Random Processes. W. B. Saunders, Philadelphia.Google Scholar
Glynn, P. W. (1982) On the Markov property of the GI/G/∞ Gaussian limit. Adv. Appl. Prob. 14, 191194.CrossRefGoogle Scholar
Gnedenko, B. V. and Kovalenko, I. N. (1968) Introduction to Queueing Theory. Israel Program for Scientific Translations, Jerusalem.Google Scholar
Halachmi, B. and Franta, W. R. (1978) A diffusion approximation to the multi-server queue. Management Sci. 24, 522529.Google Scholar
Halfin, S. and Whitt, W. (1981) Heavy-traffic limits for queues with many exponential servers. Operat. Res. 29, 567588.Google Scholar
Harrison, J. M. (1978) The diffusion approximation for tandem queues in heavy traffic. Adv. Appl. Prob. 10, 886905.Google Scholar
Iglehart, D. L. (1965) Limit diffusion approximations for the many server queue and the repairman problem. J. Appl. Prob. 2, 429441.Google Scholar
Iglehart, D. L. (1968) Limit theorems for the multi-urn Ehrenfest model. Ann. Math. Statist. 39, 864876.CrossRefGoogle Scholar
Iglehart, D. L. (1973a) Weak convergence of compound stochastic processes. Stoch. Proc. Appl. 1, 1131.CrossRefGoogle Scholar
Iglehart, D. L. (1973b) Weak convergence in queueing theory. Adv. Appl. Prob. 5, 570594.Google Scholar
Iglehart, D. L. and Lalchandani, A. P. (1973) Diffusion approximations for complex repair systems. Technical Report No. 266–12, Control Analysis Corporation, 800 Welch Road, Palo Alto, California.Google Scholar
Jagers, P. (1968) Age-dependent branching processes allowing immigration. Theory Prob. Appl. 13, 225236.CrossRefGoogle Scholar
Kamae, T., Krengel, U. and O'Brien, G. L. (1977) Stochastic inequalities on partially ordered spaces. Ann. Prob. 5, 899912.Google Scholar
Kaplan, N. (1975) Limit theorems for a GI/G/ queue. Ann. Prob. 3, 780789.CrossRefGoogle Scholar
Keilson, J. and Ross, H. F. (1975) Passage time distributions for Gaussian Markov (Ornstein–Uhlenbeck) statistical processes. Selected Tables in Math. Statist. 3, 233327.Google Scholar
Kelly, F. P. (1976) Networks of queues. Adv. Appl. Prob. 8, 416432.Google Scholar
Kingman, J. F. C. (1962) On queues in heavy traffic. J. R. Statist. Soc. B 24, 383392.Google Scholar
König, D., Schmidt, V. and Stoyan, D. (1976) On some relations between stationary distributions of queue lengths and imbedded queue length in G/G/s systems. Math. Operations-forsch. Statist. 7, 577586.Google Scholar
Lemoine, A. J. (1978) Networks of queues—a survey of weak convergence results. Management. Sci. 24, 11751193.CrossRefGoogle Scholar
McNeil, D. R. (1973) Diffusion limits for congestion models. J. Appl. Prob. 10, 368376.Google Scholar
McNeil, D. R. and Schach, S. (1973) Central limit analogues for Markov population processes. J. R. Statist. Soc. B 35, 123.Google Scholar
Miller, D. R. (1972) Existence of limits in regenerative processes. Ann. Math. Statist. 43, 12751282.Google Scholar
Miller, D. R. and Sentilles, F. D. (1975) Translated renewal processes and the existence of a limiting distribution for the queue length of the GI/G/s queue. Ann. Prob. 3, 424439.Google Scholar
Newell, G. F. (1973) Approximate Stochastic Behavior of n-Server Service Systems with Large n. Lecture Notes in Economics and Mathematical Systems 87, Springer-Verlag, Berlin.CrossRefGoogle Scholar
O'Brien, G. L. (1975) The comparison method for stochastic processes. Ann. Prob. 3, 8088.CrossRefGoogle Scholar
Pakes, A. G. and Kaplan, N. (1974) On the subcritical Bellman–Harris process with immigration. J. Appl. Prob. 11, 652668.Google Scholar
Reiman, M. I. (1977) Queueing networks in heavy traffic. Technical Report No. 76, Department of Operations Research, Stanford University.Google Scholar
Ross, S. M. (1970) Applied Probability Models with Optimization Applications. Holden-Day, San Francisco.Google Scholar
Schach, S. (1971) Weak convergence results for a class of multivariate Markov processes. Ann. Math. Statist. 42, 451465.Google Scholar
Schassberger, R. (1973) Queueing Theory (in German). Springer-Verlag, Berlin.Google Scholar
Stroock, D. W. and Varadhan, S. R. S. (1979) Multidimensional Diffusion Processes. Springer-Verlag, New York.Google Scholar
Whitt, W. (1972) Embedded renewal processes in the GI/G/s queue. J. Appl. Prob. 9, 650658.CrossRefGoogle Scholar
Whitt, W. (1980) Some useful functions for functional limit theorems. Math. Operat. Res. 5, 6785.Google Scholar
Whitt, W. (1981) Comparing counting processes and queues. Adv. Appl. Prob. 13, 207220.Google Scholar
Whitt, W. (1981a) Existence of limiting distributions in the GI/G/s queue. Math. Operat. Res. 6.Google Scholar