TR-IIS-05-023 Fulltext
Real-Time Scheduling by Cascading
Ray-I Chang, Ruei-Chuan
Chang, Jan-Ming Ho
Abstract
Real-time scheduling is important for modern computer
systems to support increasingly popular multimedia applications. In this paper,
we consider a simple video server that receives the commands from clients and
sends the video data without error occurred. In the video server, there is one
parent thread for dealing with the arrival video tasks. After receiving a new
video task from a client, a new child thread is created to determinate the real-time
requirements for disk access. Based on the results of traffic smoothing and
the sizes of disk blocks, the child thread sends real-time disk requests to
the system. Then, a multi-segment cascade scheme is applied to implement the
real-time disk scheduling routine on UnixWare operating systems. Both the simulation
results and the implementation results are presented for comparisons. The same
idea may be extended to handle the real-time scheduling problem with both video
server and video proxy [30].