Debugging and analysis at the model level

IBM® Rational® Rhapsody® facilitates model-level debugging through animated sequence diagrams, animated statecharts, and animated activity diagrams.

Before you begin

You can step through the application at an "object-oriented granularity" (operation call, one event processing, the whole event queue) and visually observe the effect on the statechart (for example, change of active state), and on the sequence diagram (for example, message/event arrows are drawn as they are sent). These capabilities are supported by various framework elements. Stepping through an application is a good way to test the functional aspects of a system.

About this task

To use Rational Rhapsody for empirical schedulability analysis of real-time applications:

Procedure

  1. Assign estimated durations for the execution of operations.
  2. Write a driver that simulates the injection of external events into the system. The driver can be a script or a statechart that generates events.
  3. Activate the driver and the system reacts as programmed, simulating the time required to perform the operations. While running, Rational Rhapsody generates an animated sequence diagram and a time-stamped trace. You can inspect these outputs to see if the deadlines have been met.

Example

What to do next

This performance simulation can be run either on the development host or on the target machine. If you run it on a target machine, you have the advantage of measuring response times of the real target operating system. The Quality of service parameters are also useful performing a schedulability analysis.


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