1. A method comprising: storing in a memory an executable graphical model including a plurality of components including hierarchically arranged child components disposed within parent components, the child components configured to send and receive messages during execution of the graphical model in an order, the messages persist for determined time intervals between a model execution start time and a model execution end time, and have payloads that remain fixed for a given send-receive interaction; identifying, by a processor coupled to the memory: the child components configured to send and receive messages, and the determined time intervals of the messages; automatically generating, by the processor, a message view window for the graphical model, the message view window including: an execution time scale corresponding to a time of execution of the graphical model, parent lifelines corresponding to the parent components, the parent lifelines extending across the execution time scale, and a plurality of first graphical affordances associated with the parent lifelines, the plurality of first graphical affordances representing the messages, the plurality of first graphical affordances arranged in the order of the messages; and expanding a given parent lifeline corresponding to a given parent component of the executable graphical model to show child lifelines corresponding to at least two of the child components of the given parent component.