Adaptive K-PackCache: Cost-Centric Data Caching in Cloud

Abstract: Recent advances in data analytics have enabled the accurate prediction of user access patterns, giving rise to the idea of packed caching delivering multiple co accessed data items together as a bundle. This improves caching efficiency, as accessing one item often implies the need for others. Prior work has explored only 2 item pairwise packing. In this paper, we extend the concept to general K packing, allowing variable size bundles for improved flexibility and performance. We formulate the K PackCache problem from a content delivery network CDN operator perspective, aiming to minimize total cost comprising two components: transfer cost modeled as a base cost plus a linearly increasing term with the number of items packed, and memory rental cost for caching, which depends on how long and how much is stored. Overpacking increases cost due to low utility, underpacking leads to missed sharing opportunities. We propose an online algorithm, Adaptive K PackCache AKPC, which dynamically forms, merges, and splits data cliques based on user access patterns and content correlation. Our approach supports batch requests, enables approximate clique merging, and offers a formal competitive guarantee. Through extensive evaluation on the Netflix and Spotify datasets, AKPC reduces total cost by up to 63 and 55 percentage over online baselines, respectively, and achieves performance within 15 and 13 percentage of the optimal. This demonstrates its scalability and effectiveness for real world caching systems.