A method of enhancing a display of performance data in a hierarchical state diagram includes measuring a processing time P(t) for each transition action code T(t) of each hierarchical level of the hierarchical state diagram, measuring a processing time P(t) for each state of each hierarchical level of the hierarchical state diagram, and modifying the hierarchical state diagram to enlarge or decrease a width W(t) of transition lines in accordance with a ratio of processing times of all transition action codes in a same hierarchical level. The method also includes modifying the hierarchical state diagram to enlarge or decrease an area size S(x) of a state P(x) to a ratio of processing times of all states in a same hierarchical level, to enlarge or decrease a width W′(t) of an arrow representative of an EntryAction and ExitAction of a state in proportion to processing time and displaying the modified hierarchical state diagram to enhance visualization of the modified transition line width W(t), the modified area size S(x) and the modified EntryAction/ExitAction width W′(t).