Content and Geographical Locality in User-Generated Content Sharing Systems

摘要

User Generated Content (UGC), such as YouTube videos. accounts for a substantial fraction of the Internet traffic. To optimize their performance, UGC services usually rely on both proactive and reactive approaches that exploit spatial and temporal locality in access patterns. Alternative types of locality are also relevant and hardly ever considered together. In this paper, we show on a large (more than 650.000 videos) YouTube dataset that content locality (induced by the related videos feature) and geographic locality, are in fact correlated. More specifically, we show how the geographic view distribution of a video can be inferred to a large extent from that of its related videos. We leverage these findings to propose a UGC storage system that proac-tively places videos ("lose to the expected requests. Compared to a caching-based solution, our system decreases by 16% the number of requests served from a different country than that of the requesting user. and even in this case, the distance between the user and the server is 29% shorter on average.