The affected set priority ceiling protocols for real-time object-oriented concurrency control

This paper presents two concurrency control protocols for real-time object- oriented systems. One of the protocols (Affected Set Priority Ceiling Proto col) is designed for single-node systems, and the other (Distributed Affect ed Set Priorityt Ceiling Protocol) is designed for distributed systems. Bot h protocols combine features of semantic concurrency control for added conc urrency, with priority ceiling techniques for deadlock prevention and bound ing priority inversion. This paper demonstrates the properties of increased concurrency, deadlock prevention, and bounded priority inversion of both p rotocols. It also describes, for each of the new protocols, an implementati on that demonstrates its usefulness in real-time object-oriented systems.