On Netflix catalog dynamics and caching performance
Résumé
Multimedia streaming applications have substantially changed the market policy of an increasing number of
content providers that offer streaming services to the users. The
need for effective video content delivery re-fueled interest for
caching: since the Web-like workload of the 90s are not longer
fit to describe the new Web of videos, in this work we investigate
the suitability of the publicly available Netflix dataset for caching
studies. Our analysis shows that, as the dataset continuously
evolves (i) a steady state description is not statistically meaningful
and (ii) despite the cache hit ratio decreases due to the growth
of active movies in the catalog, simple caching replacement
approaches are close to the optimum given the growing skew
in the popularity distribution over the time. Additionally, we
point out that, since the dataset reports logs of movie ratings,
anomalies arise when ratings are considered to be movie views.
At the same time, we show anomalies yield conservative caching
results, that reinforces the soundness of our study.