基于任务复制的多维QoS云计算任务调度

为了满足云计算环境下用户服务质量(QoS)需求和提高虚拟资源空闲时间段的利用率，提出了一种基于任务复制的多维QoS任务调度策略。首先,构建云资源模型和用户QoS模型，然后根据虚拟资源的利用情况和QoS的满意度对虚拟机进行性能测评，选择综合性能更高的虚拟资源进行任务的分配；在任务执行时为了缩短任务的完成时间，在调度过程中引入了在空闲时间段复制父任务的方式。通过仿真实验将该算法与HEFT、CPOP进行比较，实验结果显示：当用户偏好可靠性执行时，该算法平均可靠性比HEFT和CPOP高；当用户偏好完成时间和费用花费执行时，该算法平均完成时间比HEFT和CPOP少；当用户无偏好执行时，该算法平均完成时间和平均花费均比HEFT和CPOP少。结果表明该算法能有效提高资源利用率和用户的满意度。

Multi-dimensional QoS cloud task scheduling algorithm based on task replication

Under the cloud environment, in order to take full advantage of idle time of virtual resources and meet the user's Quality of Service (QoS) requirements, a multi-dimensional QoS cloud task scheduling algorithm based on task replication was proposed. First, a cloud resource model and a user's QoS model were built. Then according to the utilization of resources and QoS satisfaction, the virtual resource with higher overall performance was chosen. Simultaneously, this algorithm duplicated a parent task in idle time to reduce the execution time. In the comparison experiments with HEFT (Heterogeneous Earliest Finish Time) and CPOP (Critical Path On a Processor), when the user's preferences perform reliability, the average reliability of the proposed algorithm was higher than that of HEFT and CPOP; when the user's preferences perform makespan and cost, the average makespan of the proposed algorithm was smaller than that of HEFT and CPOP; when the user's preferences perform nothing, the average makespan and cost of the proposed algorithm was smaller than that of HEFT and CPOP. The experimental results indicate that the proposed algorithm can improve satisfaction of customers and utilization of resources.