Proposta de proxy de vídeo escalável com hierarquia de memória

Abstract

This work proposes the usage of a hierarchical memory model in video on demand (VoD) distribution servers. From a study about characteristics of the application and different memory technologies, as well as state-of-the-art techniques for dynamic proxy management, a novel technique called Hierarchical Collapsed Cooperative Memory (MCCH) is presented. This approach is based on a technique called Collapsed Cooperative Memory (MCC), which only uses RAM to cache data received from the system server, adapting it with the inclusion of a second memory level as a victim cache on the proxy memory hierarchy. In order to evaluate performance of MCCH, an analytical model and a discrete events simulator were developed to allow both a quantitative and qualitative analysis. The simulation results for just one cache level were corroborated with cross-validation against data from the model and results presented in previous works about MCC. The results of analyses provide ways to verify that the scenarios consisting of a two-level cache proxy memory hierarchy, the MCCH showed similar performance, though using a lower cost comparing to the MCC for the same proxy resources percentages. Besides such main comparison, this study also proposes and evaluates an optimization on the link slot creation process of the original single-level MCC technique that leads to better performance.