Mobile Edge Computing Networks: Online Low-Latency and Fresh Service Provisioning
Yuhan Yi, Guanglin Zhang, Hai Jiang
TL;DR
The paper tackles online provisioning of low-latency and fresh edge services in MEC by jointly optimizing service caching, task offloading, and resource allocation under AoI constraints. It introduces a Lyapunov-based framework that decouples the original NP-hard, long-horizon problem into per-slot subproblems, solved via P1(a) (convex bandwidth allocation) and P1(b) (AoI-aware decisions). A novel online integrated optimization–DRL (OIODRL) approach then combines a QCQP+SDR optimization stage to generate rough caching/downloading guidance with a Clip-PPO2 learning stage to finalize offloading, caching, and CPU allocations, achieving near-optimal performance with strong stability guarantees (gap bounded by $B/V$). Extensive simulations show OIODRL matching OPTIMAL closely and outperforming several DRL and heuristic baselines, validating the method’s practical impact for online MEC provisioning with freshness constraints.
Abstract
Edge service caching can significantly mitigate latency and reduce communication and computing overhead by fetching and initializing services (applications) from clouds. The freshness of cached service data is critical when providing satisfactory services to users, but has been overlooked in existing research efforts. In this paper, we study the online low-latency and fresh service provisioning in mobile edge computing (MEC) networks. Specifically, we jointly optimize the service caching, task offloading, and resource allocation without knowledge of future system information, which is formulated as a joint online long-term optimization problem. This problem is NP-hard. To solve the problem, we design a Lyapunov-based online framework that decouples the problem at temporal level into a series of per-time-slot subproblems. For each subproblem, we propose an online integrated optimization-deep reinforcement learning (OIODRL) method, which contains an optimization stage including a quadratically constrained quadratic program (QCQP) transformation and a semidefinite relaxation (SDR) method, and a learning stage including a deep reinforcement learning (DRL) algorithm. Extensive simulations show that the proposed OIODRL method achieves a near-optimal solution and outperforms other benchmark methods.
