Model-Driven Trace Diagnostics for Pattern-based Temporal Specifications

Offline trace checking tools check whether a specification holds on a log of events recorded at run time; they yield a verification verdict (typically a boolean value) when the checking process ends. When the verdict is false, a software engineer needs to diagnose the property violations found in the trace in order to understand their cause and, if needed, decide for corrective actions to be performed on the system. However, a boolean verdict may not be informative enough to perform trace diagnostics, since it does not provide any useful information about the cause of the violation and because a property can be violated for multiple reasons. The goal of this paper is to provide a practical and scalable so- lution to solve the trace diagnostics problem, in the settings of model-driven trace checking of temporal properties expressed in TemPsy, a pattern-based specification language. The main contributions of the paper are: a model-driven approach for trace diagnostics of pattern-based temporal properties expressed in TemPsy, which relies on the evaluation of OCL queries on an instance of a trace meta-model; the implementation of this trace diagnostics procedure in the TemPsy-Report tool; the evaluation of the scalability of TemPsy-Report, when used for the diagnostics of violations of real properties derived from a case study of our industrial partner. The results show that TemPsy-Report is able to collect diagnostic information from large traces (with one million events) in less than ten seconds; TemPsy-Report scales linearly with respect to the length of the trace and keeps approximately constant performance as the number of violations increases.