This paper aims at describing Carnival, a movie on demand system that provides Movie on demand service by implementing low cost storage architecture for movie storage server. Carnival uses personal computers with ordinary configuration, as movie storage servers. Since RAM will become a major bottleneck in such storage servers, hence optimization from the view of memory should be a primary concern. The solution described in this paper proposes a movie file system which minimizes the RAM requirements of the movie storage servers. The proposed file system provides various VCR functionalities like forward, rewind pause and play without any additional RAM requirements.