Service Placement and Bandwidth Allocation for MEC-enabled Mobile Cloud Gaming

Mobile cloud gaming (MCG), which is potential to deliver high-quality gaming experience to users anywhere and anytime, suffers from tremendous wide-area traffic and long network delays. Mobile edge computing (MEC), where cloud computing capabilities are pushed to the network edge, can help by providing gaming services in the proximity to users. However, since the quality of experience (QoE), i.e., the gaming experience, is easily impaired by long network delays and low frame rates, the performance of MEC-enabled MCG highly depends on the placement of gaming services and the allocation of related bandwidth. Furthermore, due to the erratic mobility of users, migrating services to follow such mobility decreases the impairment but incurs extra system cost, leading to the performance-cost tradeoff. To address these challenges, in this paper, we jointly investigate service placement and bandwidth allocation for MEC-enabled MCG. Considering the system dynamics, we propose to minimize the QoE impairment in a long time scope under a cost constraint for long-term migrations. To solve the problem, we develop an online two-layer iterative algorithm OnTrial. Rigorous theoretical analyses demonstrate that OnTrial achieves a near-optimal performance and bounds the potential violation of the migration cost constraint. Simulation results show that OnTrial outperforms other algorithms by at least 25% on the long-term QoE impairment.