Article contents
STOCHASTIC BATCH SCHEDULING AND THE “SMALLEST VARIANCE FIRST” RULE
Published online by Cambridge University Press: 22 October 2007
Abstract
Consider a single machine that can process multiple jobs in batch mode. We have n jobs and the processing time of job j is a random variable Xj with distribution Fj. Up to b jobs can be processed simultaneously by the machine. The jobs in a batch all have to start at the same time and the batch is completed when all jobs have finished their processing (i.e., at the maximum of the processing times of the jobs in that batch). We are interested in two objective functions, namely the minimization of the expected makespan and the minimization of the total expected completion time. We first show that under certain fairly general conditions, the minimization of the expected makespan is equivalent to specific deterministic combinatorial problems, namely the Weighted Matching problem and the Set Partitioning problem. We then consider the case when all jobs have the same mean processing time but different variances. We show that for certain special classes of processing time distributions the Smallest Variance First rule minimizes the expected makespan as well as the total expected completion time. In our conclusions we present various general rules that are suitable for the minimization of the expected makespan and the total expected completion time in batch scheduling.
- Type
- Research Article
- Information
- Probability in the Engineering and Informational Sciences , Volume 21 , Issue 4 , October 2007 , pp. 579 - 595
- Copyright
- Copyright © Cambridge University Press 2007
References
- 6
- Cited by