Evaluation of scheduling algorithms for resources with high set-up time

Abstract

Tapes and removable disks are considered resources with high set-up time. When dealing with such resources, a simple and apparently appealing heuristics consists of scheduling jobs to minimize the total number of set-up. In this paper, we examine the validity of such approach, developing both a probabilistic and a simulation model. For sake of concreteness, the example considered refers to a system consisting of a tape library and a limited number of drives. The results obtained are discussed and the problem of applying the proposed evaluation technique to computer centers with different library frequency distributions is examined.