On-Line Scheduling of Parallel Jobs
نویسنده
چکیده
Abstract. Online scheduling of parallel jobs is a problem where jobs with unit processing time and integer release times and deadlines are scheduled on a set of processors. Every job requests certain number of processors. In our setting processors are organized as a hypercube and jobs are scheduled on subhypercubes of the hypercube. The objective is to schedule as many jobs as possible between their release times and deadlines. The problem is online, that is an algorithm has to make decisions about current schedule without knowledge of future jobs that are revealed at their release time. We present a lower bound of 4/3 for a competitive ratio of every deterministic algorithm. We also present Profit-Greedy Algorithm for a case of two processors and we prove that its competitive ratio is 3/2.
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