视频点播环境下的缓存算法研究

Study and Implementation on Cache Algorithms

在视频点播环境下,用户的视频访问速度的提高是提升用户体验的关键。用户的视频访问速度与服务器响应速度、网络传输等相关,其中服务器对用户请求的响应是主要因素。作为视频点播环境下提高用户访问速度的一种重要手段,缓存技术一直是工业界和学术界关注的焦点。针对LRU、LRU、LRFU、SC等经典算法进行对比分析,并结合在视频点播环境下的模拟数据和某运营商提供的实际数据进行实证研究,观察各算法的实际表现。分析了各算法的应用结果,发掘视频点播环境下缓存算法的选择策略,为提升视频点播系统的缓存命中率提供了理论依据。

In video on demand system,the speed of users accessing the videos is the key to improve the user experience.The speed of the users accessing the videos is related to the response speed of the servers,the net transmission and so on,among which the response speed of the servers is the main factor.As an important application to improve the user access speed in video on demand system,the cache technology attracts much attention in industry and academia.This paper focused on the comparison and analysis of LRU,LFU,LRFU,SC and some other classic algorithms.Simulated data and actual data were both used to demonstrate and research.The actual performance of the algorithms was observed in order to help select the right cache algorithm in video on demand system,which provides theory evidence to improve the hit ratio of cache in video on demand system.