Analysis of scheduling algorithms for master–slave systems

The master–slave paradigm finds important applications in many industrial settings. In the master–slave model considered in this paper a set of jobs is to be processed by a system of processors. Each job consists of a preprocessing task, a slave task and a postprocessing task that must be executed in this order. The pre- and postprocessing tasks are to be processed by a master processor, whereas the slave task is processed by a slave processor. We consider three different specifications for the relative order of pre- and postprocessing tasks; namely order preserving sequences, reverse order sequences, and sequences where no order constraint is imposed. For the problem of minimizing makespan in master–slave systems with multiple masters, we develop heuristic algorithms with good bounded performance, for all three order specifications. Our computational results indicate that the average performance of our heuristics is near optimal. Furthermore, we identify the production environment and workload characteristics that favor each order specification.