Abstract
The tremendous progress of hardware technology has made the realization of multimedia application. In this paper, we first design and implement a distributed multimedia-on-demand application. As the huge volumes of media data and lots of viewers have to be supported, a distributed architecture is thus adopted for our system. Besides, to accommodate the limited bandwidth of disk subsystem and jitter-free characteristics of multimedia playback, we also propose a disk scheduling scheme for real-time I/O retrieval in a multimedia server. Previously, by DM-SCAN, groups of tasks that can be rescheduled under real-time constraints are selected. They are called MSGs (Maximum-Scannable-Groups). In this paper, an enlarged-MSG (E-MSG) is proposed to further expand the MSG concept. By removing excess constraints on MSG, E-MSG merges several MSGs as a new reschedulable group. Experiment results show that E-MSG scheme is superior to MSG in the obtained disk throughput