Global State Detection Using Network Preemption

Gang scheduling provides shorter response time and enables interactive parallel programming. To utilize processor resources on interactive parallel programs, global state of distributed parallel processes should be detected. This problem is well-known as \distributed termination problem." In this paper, we propose a practical method to detect a global state of distributed processes. There are two key methods to detect a global state described in this paper. One is by network preemption and the other is by combining global state detection with gang scheduling. The overhead for the detection of a global state is negligible. To implement our scheme, we extend our gang scheduler, SCore-D, to an operating system by implementing a system-call mechanism. We con rmed that our proposed global state detection scheme is very useful on SCore-D.