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The optimality of LEPT in parallel machine scheduling

Published online by Cambridge University Press:  14 July 2016

Cheng-Shang Chang*
Affiliation:
IBM T. J. Watson Research Center
Rhonda Righter*
Affiliation:
Santa Clara University
*
Postal address: IBM Research Division, T. J. Watson Research Center, P.O. Box 704, Yorktown Heights, NY 10598, USA.
∗∗ Postal address: Department of Decision and Information Sciences, Santa Clara University, Santa Clara, CA 95053, USA.

Abstract

We consider preemptive scheduling on parallel machines where the number of available machines may be an arbitrary, possibly random, function of time. Processing times of jobs are from a family of DLR (decreasing likelihood ratio) distributions, and jobs may arrive at random agreeable times. We give a constructive coupling proof to show that LEPT stochastically minimizes the makespan, and that it minimizes the expected cost when the cost function satisfies certain agreeability conditions.

Type
Research Papers
Copyright
Copyright © Applied Probability Trust 1994 

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