A system and method for monitoring the performance and execution flow of a target application and generating a corresponding data model are provided. The system and method comprise attaching to a thread or process of a target application and tracking the execution of subroutines using instrumentation commands. Data representing the execution flow of the various subroutines, subroutine calls, and their performance is gathered and used to generate data models representing the threads and processes of the application. The data models are optionally merged and/or pruned. A visualization of the data models is generated indicating relevant points of interest within the target application's execution flow.