一個高效能視訊伺服器管理系統平台之研製

Abstract

近年來，由於許多電腦技術的不斷演進，使得隨選視訊系統已能實際使用 在提供視訊服務的應用上；因而，如何提供一個具高效能之視訊伺服器也 愈來愈趨於重要。在本篇論文中，我們研製了一個有效的視訊伺服器管理 系統的平台雛型，其主要可分為使用者人數控制，工作排程管理，磁碟排 程管理與資料儲存管理等四大功能模組。同時，我們提出兩種視訊內容擺 放方式用以改善磁碟群組間工作不均的問題，進而達到改善伺服器的輸出 能力。透過實際系統的評估，我們的方法確實較其它類似的方法有相當優 異的效能，可以提供於此方面設計者良好的參考。此外，透過模組化的設 計方式，對於視訊伺服器管理系統的每一個功能模組，我們將得以輕易的 更改或增進其功能與方法；因而，關於伺服器上的許多方法將可以被實際 應用並驗證在我們的平台上。我們並提供一個易於操作的圖形介面，使用 者將可以方便的操作系統，而提供了一個良好的教學研究與技術轉移的雛 型。詳細的設計原理與效能評估將在論文以後的章節中一一介紹。 Recently, rapid progression in computer technologies has drivenVideo on Demand (VOD) system from concept to reality. Thus, a high performance video server system plays more and more importantrole in this area. In this thesis, a prototype of video server management system has been proposed and developed which contains four main function module, named admission control module, job schedule module, disk schedule module and data placement module. In this platform, we have also proposed and developed two content placement methods called content segment striping policy (CSSP) and dynamic segment swapping policy (DSSP) to balance the load of the disks, thereby helping to solve a performance problem crucial to archiving maximal server throughput. According to our preliminary performance evaluations, we have found that our policies decrease the reject probability of requests and improve the service capacity of video server (more than 90% of maximal service capacity). Besides, due to the modular design, each function module of our platform can be expanded or enhanced easily. By using our platform, many design issues of video server can be explored and improved. We have also implemented a friendly GUI such that user can manipulate our platform conveniently. The detailed information about design principles and performance evaluations will be described in the literature.