The Design Of Message Middleware And The Research Of Real-Time Schedule

Currently, open system technology is widespread used in the area of information technology. Applying open system technology can develop, integrate, upgrade and maintain application system conveniently. Therefore the cost of building such system is reduced and the productivity is improved. The asynchronous message transmission is the effective solution to the open system. To solve the problems, message queue middleware comes out. Its prominent function lie in the right aspects: integrates the distributed applications and transmits the asynchronous message. However, existing open system technology can not support applications with non-functional requirements, such as real-time performance, which are no less important than the functional requirements. At the same time, the coverage of real-time application is increasingly broadening. From traditional industrial control systems to newly emerged networked multimedia systems, the operations with time limitation are needed in them. These systems are required to be opening in order to shorter the development cycle and to reduce the cost. Therefore, it is necessary to study how to integrate real-time application with open system architecture. The dissertation is devoted to show the research on this subject through theoretic and practice. The main contribution is as follows: the exordium part expounds the challenge of distributed applications are facing, brings forward the concept of real-time message middleware and introduce the concerning technologies and products of the domestic and overseas. The following part introduce of CORBA, real-time CORBA and event service, under which we construct a real-time message middleware prototype. Concerning the real-time scheduling algorithm, this dissertation has introduced some classical scheduling algorithm, and in the end I will introduce a predictive disposal to EDF scheduling algorithm.