Task scheduling with communication delays is an NP-hard problem. Some previous attempts at finding optimal solutions to this problem have used branch-and-bound state-space search, with promising results. Duplication is an extension to the task scheduling model which allows tasks to be executed multiple times within a schedule, providing benefits to schedule length where this allows a reduction in communication costs. This article proposes the first approach to state-space search for optimal task scheduling with task duplication. Also presented are new definitions for important standard bounding metrics in the context of duplication. An extensive empirical evaluation shows that the use of duplication significantly increases the difficulty of optimal scheduling, but the proposed approach also gives certainty that a large proportion of task graphs can be scheduled more effectively when duplication is allowed, and permits to quantify the exact advantage.

中文翻译：

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在具有通信延迟的最优任务调度中集成任务复制

具有通信延迟的任务调度是一个 NP-hard 问题。之前为该问题寻找最佳解决方案的一些尝试使用了分支定界状态空间搜索，并取得了可喜的结果。复制是任务调度模型的扩展，它允许任务在一个调度内执行多次，为调度长度提供好处，这可以降低通信成本。本文提出了第一种状态空间搜索方法，用于通过任务重复进行最优任务调度。还介绍了在重复上下文中重要标准边界度量的新定义。广泛的实证评估表明，使用重复显着增加了优化调度的难度，