Server scheduling on parallel dedicated machines with fixed job sequences

Abstract

We consider server scheduling on parallel dedicated machines to minimize the makespan. Each job has a loading operation and a processing operation. The loading operation requires a server that serves all the jobs. Each machine has a given set of jobs to process, and the processing sequence is known and fixed. We design a polynomial-time algorithm to solve the two-machine case of the problem. When the number of machines is arbitrary, the problem becomes strongly NP-hard even if all the jobs have the same processing length or all the loading operations require a unit time. We design two heuristic algorithms to treat the case where all the loading times are unit and analyze their performance.