基于网格的地震模拟工作流调度

Scheduling of earthquake simulation workflow based on grid facility

网格为地震模拟等大规模工作流应用提供了强大的计算能力,如何保障此类应用的软实时性要求是工作流调度问题的一个挑战.利用排队模型来描述网格资源的动态负载压力,提出了评估工作流健壮性量化指标及其计算方法.基于DAG图转换得出的任务执行优先级,根据最大健壮性优先的思想,确定了执行工作流子任务的候选资源;将工作流全局截止时间划分问题描述为一个约束下的非线性规划问题并通过已有方法求解该问题,提出了工作流全局截止时间动态划分方法;最后,提出了一种健壮性增强的地震模拟工作流调度算法RESAESW.仿真实验采用实际地震模拟工作流应用和实际系统数据来验证提出算法的性能表现,实验结果表明本文算法在网格环境的自适应性和地震模拟工作流应用的截止时间要求方面优于其他两个实际网格系统中的调度算法.

Grid provides large computing capability for programming scientific workflow such as earthquake simulation.How to guarantee soft real-time requirement of these applications is a challenging problem.Queuing model is utilized to describe volatile workload of Grid resource and then we proposed a metric that quantifying workflow robustness.According to thinking of biggest workflow robustness first,candidate resource for each workflow task is selected in order of their priorities calculated from DAG structure.We model workflow global deadline division as a constrained non-linear programming problem and resort to an interior point algorithm to solve it,and present a dynamic deadline division method.Then a Robustness Enhanced Scheduling Algorithm for Earthquake Simulation Workflow（RESAESW） is devised from resource selection and global deadline division.We conducted extensive simulations using a case for earthquake simulation workflow and real-world Grid workload to validate our algorithm.Experimental results show that our algorithm has better performance on adaption to dynamic Grid and application＇s deadline guarantee,and outperforms two other algorithms used in real Grid system.