General queueing networks with priorities. Maximum entropy analysis of general queueing network models with priority preemptive resume or head-of-line and non-priority based service disciplines.

Description

Priority based scheduling disciplines are widely used by existing
computer operating systems. However, the mathematical analysis and
modelling of these systems present great difficulties since priority
schedulling is not compatible with exact product form solutions of
queueing network models (QNM's). It is therefore, necessary to employ
credible approximate techniques for solving QNM's with priority
classes.
The principle of maximum entropy (ME) is a method of inference
for estimating a probability distribution given prior information in
the form of expected values. This principle is applied, based on
marginal utilisation, mean queue length and idle state probability
constraints, to characterise new product-form approximations for
general open and closed QNM's with priority (preemptive-resume,
non-preemtive head-of-line) and non-priority
(first-come-first-served, processor-sharing, last-come-first-served
with, or without preemtion) servers. The ME solutions are interpreted
in terms of a decomposition of the original network into individual
stable GIG11 queueing stations with assumed renewal arrival
processes. These solutions are implemented by making use of the
generalised exponential (GE) distributional model to approximate the
interarrival-time and service-time distributions in the network. As a
consequence the ME queue length distribution of the stable GE/GEzl
priority queue, subject to mean value constraints obtained via
classical queueing theory on bulk queues, is used as a 'building
block' together with corresponding universal approximate flow
formulae for the analysis of general QNM's with priorities. The
credibility of the ME method is demonstrated with illustrative
numerical examples and favourable comparisons against exact,
simulation and other approximate methods are made. / Algerian government

Links & Downloads

1. http://hdl.handle.net/10454/4214

Tags

Scheduling discipline

Priority class

Maximum entropy

Preemptive resume

Head-of-line

Generalised exponential

Queueing network

Additional Fields

Identifer	oai:union.ndltd.org:BRADFORD/oai:bradscholars.brad.ac.uk:10454/4214
Date	January 1989
Creators	Tabet Aouel, Nasreddine
Contributors	Kouvatsos, Demetres D.
Publisher	University of Bradford, Department of Computing
Source Sets	Bradford Scholars
Language	English
Detected Language	English
Type	Thesis, doctoral, PhD
Rights	<a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/"><img alt="Creative Commons License" style="border-width:0" src="http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png" /></a><br />The University of Bradford theses are licenced under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/">Creative Commons Licence</a>.