De-Duplicated Hierarchical Offloading in Vehicular Edge Computing With Task Dependencies

In Vehicular Edge Computing (VEC), most tasks require high real-time and energy requirements, but the mobility of vehicles and the difficulty of intelligent computing make it hard to meet these requirements. Due to the fact that most VEC tasks can be decomposed into smaller granularity, based on the dependencies between small subtasks, the repetition of tasks can be reduced, thereby improving task completion rates. In this work, we explore the dependencies of subtasks in different applications and design a two-stage Multi-hop Clustering De-duplication Offloading (MCDO) mechanism. Firstly, MCDO gives a Multi-hop Two Layer Clustering (MTLC) algorithm to divide clusters based on similarities between different tasks. Based on this, MCDO further design a De-duplication Logical Hierarchical Offloading (DLHO). DLHO forms a Directed Acyclic Graph (DAG) of de-duplicated subtasks in each cluster, and offloads these subtasks in a logical hierarchical manner. Simulation results show that, compared to existing approaches PC5-GO, FedEdge and MD-TSDQN, MCDO can achieve a minimum improvement of 15.1% in terms of latency and 20.8% in terms of energy consumption.