基于可靠性的云工作流调度策略

经过对已有云工作流调度算法中可靠性问题进行分析研究，针对一些算法在任务调度过程中只考虑提高整个工作流的可靠性而牺牲了时间或增加花费的问题，结合云计算的特点，提出一种基于可靠性的工作流调度策略。该策略结合了工作流中任务的可靠性，充分考虑任务的优先顺序并结合复制的思想，在减少传输过程失败率的同时降低传输时间，使整个工作流在降低完成时间的同时，提高整体可靠性。通过实验和分析表明，通过该策略云工作流在不同任务数和通信运算比（CCR）的可靠性比异态最早结束时间算法（HEFT）算法及其改进算法--SHEFTEX都有所提升，完成时间比HEFT算法有所减少。

Reliability-aware workflow scheduling strategy on cloud computing platform

Through the analysis and research of reliability problems in the existing workflow scheduling algorithm, the paper proposed a reliability-based workflow strategy concerning the problems in improving the reliability of the entire workflow by sacrificing efficiency or money in some algorithms. Combining the reliability of tasks in workflow and duplication ideology, and taking full consideration of priorities among tasks, this strategy lessened failure rate in transmitting procedure and meantime shortened transmit time, so it not only enhanced overall reliability but also reduced makespan. Through the experiment and analysis, the reliability of cloud workflow in this strategy, tested by different numbers of tasks and different Communication to Computation Ratios (CCR), was proved to be better than the Heterogeneous Earliest-Finish-Time (HEFT) algorithm and its improved algorithm named SHEFTEX, including the superiority of the proposed algorithm over the HEFT in the completion time.