RTC-THREADS - A USER-LEVEL REAL-TIME THREADS PACKAGE FOR MULTIMEDIA SYSTEMS

In forthcoming multimedia environments, continuous-media data, such as video and audio data, will be used by a variety of multimedia applica tions. Multimedia applications require efficient and flexible support from real-time operating systems. This is because the changes in syste m and network loads require dynamic management of real-time thread beh avior. If threads are implemented at the user level, operations on thr eads can be processed at the user level, and the efficient management of threads becomes possible by avoiding kernel interventions. Thus, we can provide an effective platform for multimedia applications. The go al of our work is to realize high-performance user-level real-atime th reads which satisfy the above requirements of multimedia systems. In t his paper we describe the design and implementation of a user-level re al-time threads package, called RTC-Threads, which is being developed on the RT-Mach microkernel. The results of performance evaluations sho w that our user-level real-time threads outperform real-time kernel-pr ovided threads, which are implemented in the microkernel, in terms of efficiency and accuracy.