截止时间约束下独立网格任务的协同调度模型

摘要

针对网格环境中任务实时性难于保证的问题,提出一种截止时间保证度的计算方法,用于量化分析资源协同调度对任务实时约束的影响,并设计和实现了一个可扩展的协同调度模型,允许系统动态选择截止时间保证度最优的协同调度方案.实验结果显示,截止时间保证度指标可以较为准确地量化调度决策对任务实时约束的满足程度,从而为实时网格任务调度决策的最优化提供可靠依据；基于混合策略的调度模型则能综合已有协同调度策略的优点,为实时网格任务提供可靠的服务质量保证.%To address the issue of task co-schedule with deadline constraint in grids, a metric called probability of deadline guarantee is proposed to quantitatively evaluate the deadline-guarantee of a co-scheduling scheme. Based on this metric,an extensible co-scheduling framework is implemented, which combines multiple policies to obtain the optimal deadline guarantee.Extensive experiments are conducted to examine the performance of the proposed model. The results show that the probability of deadline guarantee metric can accurately quantify the degree of deadline guarantee provided by a specific co-scheduling scheme, which in turn provides an enhanced QoS for those applications with deadline constraint.