## The Annals of Applied Probability

### The critical greedy server on the integers is recurrent

#### Abstract

Each site of $\mathbb{Z}$ hosts a queue with arrival rate $\lambda$. A single server, starting at the origin, serves its current queue at rate $\mu$ until that queue is empty, and then moves to the longest neighbouring queue. In the critical case $\lambda =\mu$, we show that the server returns to every site infinitely often. We also give a sharp iterated logarithm result for the server’s position. Important ingredients in the proofs are that the times between successive queues being emptied exhibit doubly exponential growth, and that the probability that the server changes its direction is asymptotically equal to $1/4$.

#### Article information

Source
Ann. Appl. Probab., Volume 29, Number 2 (2019), 1233-1261.

Dates
Revised: August 2018
First available in Project Euclid: 24 January 2019

https://projecteuclid.org/euclid.aoap/1548298940

Digital Object Identifier
doi:10.1214/18-AAP1434

Mathematical Reviews number (MathSciNet)
MR3910027

Zentralblatt MATH identifier
07047448

#### Citation

Cruise, James R.; Wade, Andrew R. The critical greedy server on the integers is recurrent. Ann. Appl. Probab. 29 (2019), no. 2, 1233--1261. doi:10.1214/18-AAP1434. https://projecteuclid.org/euclid.aoap/1548298940

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