SAFE: Intelligent Online Scheduling for Collaborative DNN Inference in Vehicular Network

Recent years have witnessed a widespread use of deep neural networks (DNNs) in providing various intelligent services, and vehicular networks are no exception. Given the limited computing capabilities of vehicles, collaborative vehicle-edge DNN inference has emerged as a viable alternative. This approach employs DNN partitioning, where a part of DNN is computed on vehicles, and the other part on the edge, e.g., roadside unit (RSU), aiming to enhance the inference accuracy and reduce the inference latency. In this setting, deriving an optimal DNN partitioning scheme becomes critical, yet challenging given the constant movement of vehicles and the highly dynamic wireless connections. Furthermore, vehicles may move out of the signal coverage of an RSU, making it difficult to receive the inference results. To this end, we propose a two-stage intelligent scheduling framework named Soft Actor-critic for discrete actions (SAC-D) based collaborative DNN inference FramEwork (SAFE). SAFE engages multiple RSUs to assist vehicles in completing inference tasks sequentially and ensuring reliable data transmission. It can learn the dynamic vehicular network and make scheduling decisions to minimize the overall latency of vehicle inference tasks. Extensive experimental results show that SAFE can reduce up to 80% of the overall latency with a lower failure rate, compared to four baselines.