REACH: Reinforcement Learning for Adaptive Microservice Rescheduling in the Cloud-Edge Continuum
Xu Bai, Muhammed Tawfiqul Islam, Rajkumar Buyya, Adel N. Toosi
TL;DR
This work tackles latency-sensitive microservice applications in the cloud–edge continuum by introducing REACH, an RL-based rescheduling framework that incrementally updates only necessary microservice placements to minimize end-to-end latency. Using PPO in a custom CEEnv simulator, REACH learns policies that adapt to resource heterogeneity and network delays, then deploys via a Kubernetes plugin to a real testbed. Experiments show significant latency reductions and improved stability under node failures and traffic surges, with manageable online overhead and rapid training in simulation. The approach demonstrates practical applicability for real-world cloud–edge environments and lays groundwork for multi-objective extensions such as energy and bandwidth optimization.
Abstract
Cloud computing, despite its advantages in scalability, may not always fully satisfy the low-latency demands of emerging latency-sensitive pervasive applications. The cloud-edge continuum addresses this by integrating the responsiveness of edge resources with cloud scalability. Microservice Architecture (MSA) characterized by modular, loosely coupled services, aligns effectively with this continuum. However, the heterogeneous and dynamic computing resource poses significant challenges to the optimal placement of microservices. We propose REACH, a novel rescheduling algorithm that dynamically adapts microservice placement in real time using reinforcement learning to react to fluctuating resource availability, and performance variations across distributed infrastructures. Extensive experiments on a real-world testbed demonstrate that REACH reduces average end-to-end latency by 7.9%, 10%, and 8% across three benchmark MSA applications, while effectively mitigating latency fluctuations and spikes.
