Some Inequalities for Single Server Queues
نویسندگان
چکیده
The expected wait in the Gi/G/1 queue is related to the mean and variance of the idle time. For arrival distributions which are 1FR or have mean residual life bounded by r-, simple bounds are obtained which A. give, for example, the expected number in queue to within at most one customer. By equating input with output, relations between random variables are used to obtain expressions foi the moments of the waiting time in terms of moments of the inter-arrival, service, and idle time distributions. By bounding the idle time moments, bounds are obtained on the mean and variance of the waiting time, the mean length of a busy period, and the probability an arrival finds the system empty. Bounds on the mean wait lead to bounds on the expected virtual wait. Similar results are obtained for some generalizations of the Gl/G/1 queue, including batch arrivals, batch service and priority queues. Queues where the first customer in each busy period has some added delay are also considered. Some preliminary results for tandem queues are given. ai ^^**w«-*rav*si*rqF%pmpHmf?*^' i^"*^******•—-^^^-.r^^s^^^^^u:,^.^. * ■^j^F!i.^-0^«Wg^^pW^;^aaCTr.
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