文献类型：期刊文献

英文题名：QoS-Aware Task Placement With Fault-Tolerance in the Edge-Cloud

作者：Sun, Huaiying[1,2];Yu, Huiqun[1,3];Fan, Guisheng[1];Chen, Liqiong[4]

机构：[1]East China Univ Sci & Technol, Dept Comp Sci & Engn, Shanghai 200237, Peoples R China;[2]Shanghai Key Lab Comp Software Evaluating & Testi, Shanghai 201112, Peoples R China;[3]Shanghai Engn Res Ctr Smart Energy, Shanghai 200120, Peoples R China;[4]Shanghai Inst Technol, Dept Comp Sci & Engn, Shanghai 201418, Peoples R China

年份：2020

卷号：8

起止页码：77987

外文期刊名：IEEE ACCESS

收录：;EI(收录号：20202108682981);WOS:【SCI-EXPANDED(收录号:WOS:000531906600027)】；

基金：This work was supported in part by the NSF of China under Grant 61772200 and Grant 61702334, in part by the Shanghai Municipal Natural Science Foundation under Grant 17ZR1406900 and Grant 17ZR1429700, in part by the Educational Research Fund of ECUST under Grant ZH1726108, in part by the Collaborative Innovation Foundation of Shanghai Institute of Technology under Grant XTCX2016-20, and in part by the Humanities and Social Science Research Planning Fund of the Education Ministry of China under Grant 15YJCZH201.

语种：英文

外文关键词：Task analysis; Fault tolerance; Fault tolerant systems; Quality of service; Scheduling; Real-time systems; Scheduling algorithms; Edge-cloud; QoS; fault-tolerance; time constraint; primary-backup

摘要：The geographically dispersed resources and ever-changing context incur unique heterogeneity, potential fragility, and vulnerability of an edge-cloud system. Thus, the reliability guarantee of services in the edge-cloud is critical. This paper firstly proposes a QoS-aware scheduling model with fault-tolerance in the edge-cloud, which extends the traditional primary-backup (PB) fault-tolerant model to improve the service reliability in the edge-cloud with the time constraints of tasks being satisfied. Then, a QoS-aware fault-tolerant scheduling algorithm including primary copy placement, backup copy placement and an adjustment mechanism is proposed to improve the QoS levels of tasks in the edge-cloud. The primary copy placement is to guarantee the earlier execution of the primary copy of a task to better satisfy the time requirements of tasks. The backup copy placement is to ensure the later execution of the backup copy of a task, reducing the overlapping of the two copies of a task, realizing the improvement of the resource utilization in the edge-cloud under the condition of redundancy and deadline requirements of tasks. The adjustment mechanism is triggered to rearrange the task copies of a computing node of the edge-cloud after the deallocation of a backup copy on the node, to better assist the goal-achievement of the primary and backup copy scheduling. Finally, through extensive simulation experiments with the real world taxi traces, the performance difference between the proposed method and the other four methods are evaluated. Results show that the proposed method generally outperforms the other methods in terms of guarantee ratio, average QoS level, and reliability cost.