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arXiv · 1309.2700

On the Sojourn Time Distribution in a Finite Population Markovian Processor Sharing Queue

Abstract

We consider a finite population processor-sharing (PS) queue, with Markovian arrivals and an exponential server. Such a queue can model an interactive computer system consisting of a bank of terminals in series with a central processing unit (CPU). For systems with a large population $N$ and a commensurately rapid service rate, or infrequent arrivals, we obtain various asymptotic results. We analyze the conditional sojourn time distribution of a tagged customer, conditioned on the number $n$ of others in the system at the tagged customer's arrival instant, and also the unconditional distribution. The asymptotics are obtained by a combination of singular perturbation methods and spectral methods. We consider several space/time scales and parameter ranges, which lead to different asymptotic behaviors. We also identify precisely when the finite population model can be approximated by the standard infinite population $M/M/1$-PS queue.

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BibTeXRIS

Qiang Zhen, Johan S. H. van Leeuwaarden, Charles Knessl. 2013-09-11. On the Sojourn Time Distribution in a Finite Population Markovian Processor Sharing Queue. https://arxiv.org/abs/1309.2700

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