Wait-free data sharing between periodic tasks in multiprocessor control systems

Abstract

In real-time systems, data sharing between processes is an important problem. There have been a number of methods to share data effectively. In multiprocessor real-time systems, a wait-free data-sharing method is attractive, for it can alleviate many of the problems of the traditional lock-based synchronization method. In this paper, a new algorithm for wait-free data sharing between real-time periodic tasks is introduced. The proposed algorithm is based on a pure-buffer algorithm and reduces the shared memory necessary by using the timing properties of the tasks. The method to determine the size of the shared memory required is also presented. The proposed method has been applied to Port-Interface Component Architecture for Real-time system Design, a software architecture for developing control systems using pre-compiled software components. The efficiency of the proposed method is shown when applied to a CNC system.