Event-Based Detection of Concurrency ; CU-CS-860-98

Understanding the behavior of a system is crucial in being able to modify, maintain, and improve the system. A particularly difficult aspect of some system behaviors is concur-rency. While there are many techniques to specify intended concurrent behavior, there are few, if any, techniques to capture and model actual concurrent behavior. This paper presents a technique to discover patterns of concurrent behavior from traces of system events. The technique is based on a probabilistic analysis of the event traces. Using met-rics for the number, frequency, and regularity of event occurrences, a determination is made of the likely concurrent behavior being manifested by the system. The technique is useful in a wide variety of software engineering tasks, including architecture discovery, reengineering, user interaction modeling, and software process improvement. The content of the information does not necessarily reflect the position or the policy of the Government and no official endorsement should be inferred.