Operating system support for high-performance, real-time CORBA

A broad range of applications (such as avionics, telecommunication systems, and multimedia on demand) require various types of real-time guarantees from the underlying middleware, operating systems, and networks to achieve their quality of service (QoS). In addition to providing real-time guarantees and end-to-end QoS, the underlying services used by these applications must be reliable, flexible, and reusable. Requirements for reliability, flexibility and reusability motivate the use of object-oriented middleware like the Common Object Request Broker Architecture (CORBA). However the performance of current CORBA implementations is not suitable for latency-sensitive real-time applications, including both hard real-time systems (e.g., avionics), and constrained latency systems (e.g., teleconferencing). This paper describes key changes that must be made to the CORBA specifications, existing CORBA implementations, and the underlying operating system to develop real-time ORBs (RT ORBs). RT ORBs must deliver real-time guarantees and end-to-end QoS to latency-sensitive applications. While many operating systems now support real-time scheduling, they do not provide integrated solutions. The main thesis of this paper is that advances in real-time distributed object computing can be achieved only by simultaneously integrating techniques and tools that simplify application development; optimize application, I/O subsystem, and network performance; and systematically measure performance to pinpoint and alleviate bottlenecks