English

Heavy-traffic single-server queues and the transform method

Probability 2022-06-22 v1

Abstract

Heavy-traffic limit theory deals with queues that operate close to criticality and face severe queueing times. Let WW denote the steady-state waiting time in the GI/G/1{\rm GI}/{\rm G}/1 queue. Kingman (1961) showed that WW, when appropriately scaled, converges in distribution to an exponential random variable as the system's load approaches 1. The original proof of this famous result uses the transform method. Starting from the Laplace transform of the pdf of WW (Pollaczek's contour integral representation), Kingman showed convergence of transforms and hence weak convergence of the involved random variables. We apply and extend this transform method to obtain convergence of moments with error assessment. We also demonstrate how the transform method can be applied to so-called nearly deterministic queues in a Kingman-type and a Gaussian heavy-traffic regime. We demonstrate numerically the accuracy of the various heavy-traffic approximations.

Keywords

Cite

@article{arxiv.2206.09844,
  title  = {Heavy-traffic single-server queues and the transform method},
  author = {M. A. A. Boon and A. J. E. M. Janssen and J. S. H. van Leeuwaarden},
  journal= {arXiv preprint arXiv:2206.09844},
  year   = {2022}
}
R2 v1 2026-06-24T11:57:25.125Z