Control of nondeterminism in testing distributed multithreaded programs

Distributed and multithreaded systems are usually much more complex to analyze statically or test dynamically due to the nondeterminism involved. Forcing the system to take a particular execution path manually may be fairly difficult sometimes. In this paper, we present our work in test control methods for distributed concurrent systems, and introduce the framework of our automated test control toolkit that can help users to realize some particular execution paths desired. The testing is specification-based: a test scenario is given as a pair of a test case and a control constraint expressing the partial order among certain events we are interested in. The test control is however based on a derived constraint only on shared objects. This allows us to develop more efficient test tools based on some unique code extension for different test scenarios. In our experiment, systems under testing consist of a set of processes, each in Java possibly with multiple threads, and communications among the processes are through CORBA.