I. Introduction
In recent years, the rapid development of the industrial Internet of things (IIoT) has promoted the proliferation of numerous intelligent end devices (EDs) for ubiquitous sensing and accessing. However, more and more computing-intensive and time-sensitive tasks are emerging that imposes higher requirements on computing and communication resources. For this case, edge computing (EC) which supports tasks offloading to EC servers was proposed to handle complex computing tasks and reduce the computing delay [1] – [4].