Dynamic Regret of Randomized Online Service Caching in Edge Computing

TL;DR

This paper introduces a randomized online caching algorithm for edge computing that minimizes dynamic regret in non-stationary request environments, outperforming existing policies in simulations.

Contribution

It proposes a novel randomized online algorithm with theoretical regret bounds for service caching in edge computing with non-stationary requests.

Findings

The algorithm achieves low expected dynamic regret.

It outperforms state-of-the-art policies in simulations.

The approach has low computational complexity.

Abstract

This paper studies an online service caching problem, where an edge server, equipped with a prediction window of future service request arrivals, needs to decide which services to host locally subject to limited storage capacity. The edge server aims to minimize the sum of a request forwarding cost (i.e., the cost of forwarding requests to remote data centers to process) and a service instantiating cost (i.e., that of retrieving and setting up a service). Considering request patterns are usually non-stationary in practice, the performance of the edge server is measured by dynamic regret, which compares the total cost with that of the dynamic optimal offline solution. To solve the problem, we propose a randomized online algorithm with low complexity and theoretically derive an upper bound on its expected dynamic regret. Simulation results show that our algorithm significantly outperforms other state-of-the-art policies in terms of the runtime and expected total cost.