Design And Optimization Of VOD Video Server Based On Linux System

With the high-speed development of computer networks, digital compression and storage technology, VOD service grows rapidly nowadays and has gained a great reputation for its good interactive abilities. At the time, the Internet's flourish still on its'way. More and more people do the Internet surfing to listen to the music, watch the movie and do other multimedia service activities. So it will have tremendous opportunities and vitality to develop a video server system to provide VOD services through the Internet.The application of multimedia has really a bright future, however, today's technology and products can't satisfy the customers properly with the total consider of the hardware and software requirements, the cost estimates, and the provided function categories. Main content of this paper is based on the VOD system developed in the Windows platform, generally speaking , it contains the following works:Firstly, give an implementation way to migrate the Windows version to the Linux system and do some improvement and optimization in the function. The former version don't provide video live service, so an implementation policy for it is given; the former version only provides the VOD service in the LAN environment, an practical way to turn it to be a system supporting streaming services is given, which is very important for the video server to provide multi-media services in the Internet.Secondly, do some researches on the ways to optimize the video server, and explains three aspects of them in detail: using a"cluster"to optimize the ext3 file system of Linux; using the"epoll"system call to improve the system's network I/O performance; using"Patching Stream recombine-able algorithm"to optimize the video stream scheduling policy. Also, the test data of the system performances before and after the optimization are given.In the last, the database sub-system is introduced, in order to solve the database access problem, a good way is to provide a"Database Access Layer"to do the work. Base on the consideration of scalability and compatibility, a feasible program is supposed to achieve this by using XML and connection pool. This program can be implemented both by C++ or Java. As far as the XML concerned, some performance test and analysis are done on different XML develop kit both for C++ and Java separately, which is a good help when the system efficiency needs to be improved.This paper applies itself to the design and optimization of high performance video server based on Linux. Its aim is to utilize the features of the Linux system in the full scale and provides higher qualities of service with lower investment..