ABSTRACT

It is quite possible that in a process set, process may be having earliest deadline but its performance contribution is low in process set. Scheduling such processes with highest priority does not carry any meaning. Majority of today’s commercial operating system schedule task based on a single parameter however recent research on flexible scheduling showed that a single parameter is not enough to express all the application requirement .In order to provide effective support to QoS management ,an algorithm for offline scheduling of communicating tasks with precedence constraints suggested on uniprocessor Since in real time system processes are communicating to each other, if any message is failed then performance of executing successor process is reduced up to some extent .Contribution of each process in process network can be evaluated offline using multistate system (MSS) analysis. This paper suggests the policy to convert task precedence and communication constraints into pseudo deadlines of task. This scheduling policy is compared with latest deadline first (LDF).Major advantage of our policy is to support cyclic process network. Where as LDF supports acyclic process network.