Assignment and scheduling real time control tasks with precedence and deadline constraint in distributed systems

摘要

The paper deals with the problem of allocate and schedule a set of periodic control tasks to process nodes in a distributed control systems working in real time environment (RT-DCS), considering timing constraints and precedence among tasks. It is described how better is to design the scheduler and control task at the same time. The method proposed guarantees the stability of the RTDCS keeping as low as possible the real time traffic over the network. The control task is modeled as a task graph which described both computation and communication requirements. A genetic algorithm is used to partition all the graphs to obtain a tentative assignments that must verify placement, schedulability, communication and precedence constraints. A benchmark is specified to demonstrate the effectiveness and feasibility of the proposed algorithm.