Summary: | 碩士 === 國立中正大學 === 資訊工程研究所 === 101 === Due to the diversity in computing capabilities of processors in heterogeneous multicore systems, it is difficult to come up with a perfect task scheduling algorithm that can avoid all processors from becoming idle at some point in time during the whole schedule. The situation becomes worse when the capabilities of processors differ by a large margin or the ratio of communication time between tasks to the computation time of tasks is very large. Nevertheless, it is this imperfection that motivates this Thesis to propose a re-scheduling scheme that leverages the characteristics of divisible tasks by partitioning the workload across two different processors so as to fill the holes (idle time slots) in the schedule. Based on the type of hole, constant or varying, different strategies are proposed, including a profiling-based partitioning and an on-the-fly partitioning. Re-scheduling based on a combination of these two strategies results in a decrease in the makespan and total amount of idle time of processors. Experiment results show that the makespan can be decreased by 14% and the total amount of idle time by 50%.
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