Evaluating CORBA latency and scalability over high-speed ATM networks

We present two contributions to the study of CORBA performance over high-speed networks. First, we measure the latency of various types and sizes of two-way client requests using a pair of widely used implementations of CORBA-Orbix 2.1 and VisiBroker for C++ 2.0. Second, we use Orbix and VisiBroker to measure the scalability of CORBA servers in terms of the number of objects they can support efficiently. These experiments extend our previous work on CORBA performance for bandwidth-sensitive applications (such as satellite surveillance, medical imaging, and teleconferencing). Our results show that the latency for CORBA implementations is relatively high and server scalability is relatively low. Our latency experiments show that non-optimized internal buffering in CORBA implementations can cause substantial delay variance, which is unacceptable in many real-time or constrained-latency applications. Likewise our scalability experiments reveal that neither Orbix nor VisiBroker can handle a large number of objects in a single server process.