The Research Of Real-Time CORBA And The Analysis And Improvement Of Real-Time Scheduling Service

Many types of applications can benefit from flexible and open middleware. CORBA is an emerging middleware standard for Object Request Brokers (ORBs) that simplifies the development of distributed applications and services. Experience with CORBA demonstrates that it is suitable for traditional RFC-style applications. However, the lack of performance optimizations and quality of service (QoS) features in conventional CORBA implementations make them unsuitable for high performance and real-time applications.Current work on real-time CORBA includes an off-line scheduled, hard real-time system based on rate-monotonic scheduling and an on-line scheduled, best-effort real-time system based on the earliest-deadline-first algorithm. The former provides QoS guarantees at the expense of run-time scheduling flexibility while the latter provides the complement.In this paper, it points out the shortages of conventional CORBA on the field of real time, the extensions of real time CORBA made to the conventional CORBA and the framework of real time CORBA by the introduce of CORBA basic concepts and the analysis of its framework as with the problems what real time applications faced. Based on all of above, this thesis expatiates the scheduling service of real time CORBA on detail and proposes a scheduling service model which provides the advantages of both, that is, QoS guarantees and run-time scheduling flexibility. Finally, some challenges for the future work are presented.