Resource synchronization for dynamic scheduling real-time CORBA

More and more computer applications are being modeled and constructed using the principals inherent to real-time distributed object systems. In 1989, the Object Management Group (OMG) formed a Real-Time Special Interest Group (RT SIG) with the goal of extending the Common Object Request Broker Architecture (CORBA) standard to include real-time specifications. This group's most recent efforts focus on the requirements of dynamic distributed real-time systems. One open problem in this area is resource access synchronization for tasks employing dynamic priority scheduling.; This dissertation presents two resource synchronization protocols that meet the requirements of dynamic distributed real-time systems as specified by the Dynamic Scheduling Real-Time CORBA (DSRT CORBA). The proposed protocols can be applied to both Earliest Deadline First (EDF) and Least Laxity First (LLF) dynamic scheduling algorithms, allow distributed nested critical sections, and avoid unnecessary runtime overhead. These protocols are based on (i) distributed resource preclaiming that allocates resources in the message-based distributed system, (ii) distributed priority inheritance that bounds local and remote priority inversion, and (iii) a distributed preemption ceiling that delimits the priority inversion time further and prevents deadlocks without extra runtime overhead.; The protocols can be efficiently implemented, providing synchronization support for dynamic priority scheduling middleware systems. Simulation experiments show the proposed protocols have better performance than one would realize by applying a protocol that utilizes dynamic priority ceiling update.