Interaction-Oriented Service Entity Placement in Edge Computing

Distributed Interactive Applications (DIAs) such as virtual reality and multiplayer online game usually require fast processing of tremendous data and timely exchange of delay-sensitive action data and metadata. This makes traditional mobile-based or cloud-based solutions no longer effective. Thanks to edge computing, DIA Service Providers (DSPs) can rent resources from Edge Infrastructure Providers (EIPs) to place service entities that store user states and run computation-intensive tasks. One fundamental problem for a DSP is to decide where to place service entities to achieve low-delay pairwise interactions between DIA users, under the constraint that the total placement cost is no more than a specified budget threshold. In this article, we formally model the service entity placement problem and prove that it is NP-complete by a polynomial reduction from the set cover problem. We present GPA, an efficient algorithm for service entity placement, and theoretically analyze its performance. We evaluated GPA with both real-world data trace-driven simulations, and observed that GPA performs close to the optimal algorithm and generally outperforms the baseline algorithm. We also output a curve showing the trade-off between the weighted average interaction delay and the budget threshold, so that a DSP can choose the right balance.