Variable bit rate MPEG video storage on parallel disk arrays

摘要: We discuss issues related to the storage and retrieval of variable bit rate (VBR) MPEG video data on parallel disk arrays for multiple simultaneous users. We store data blocks corresponding to constant real-time playback duration. Because of the VBR characteristics and the constant bandwidth read channel, disk overload occurs at peak usage periods. Our strategy to deal with disk overload is to temporarily stop service to low-priority users. To do so, we propose a number of classes of service corresponding to various probabilities of loss, during which time service is suspended. Thus, a major problem is estimating probability of loss or suspension so that a video server system can guarantee service with actual loss probabilities that do not exceed the specified thresholds at the call setup time. We propose three techniques for computing loss probabilities: histogram convolution, Central Limit Theorem, and Cramer's …