Cloud-edge computing requires applications to operate across diverse infrastructures, often triggered by cyber-physical events. Containers offer a lightweight deployment option but pulling images from central repositories can cause delays. This article presents a novel declarative approach and open-source prototype for replicating container images across the cloud-edge continuum. Considering resource availability, network QoS, and storage costs, we leverage logic programming to (i) determine optimal initial placements via Answer Set Programming (ASP) and (ii) adapt placements using Prolog-based continuous reasoning. We evaluate our solution through simulations, showcasing how combining ASP and Prolog continuous reasoning can balance cost optimisation and prompt decision-making in placement adaptation at increasing infrastructure sizes.

翻译：云边计算要求应用程序能够在多样化的基础设施上运行，通常由信息物理事件触发。容器提供了一种轻量级的部署选项，但从中央仓库拉取镜像可能导致延迟。本文提出了一种新颖的声明式方法和开源原型，用于在云边连续体中复制容器镜像。考虑到资源可用性、网络服务质量（QoS）和存储成本，我们利用逻辑编程来（i）通过答案集编程（ASP）确定最优的初始放置位置，以及（ii）使用基于Prolog的持续推理来调整放置策略。我们通过仿真评估了我们的解决方案，展示了在基础设施规模不断增长的情况下，结合ASP和Prolog持续推理如何在放置适应中平衡成本优化与快速决策。