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I submitted a paper regarding hard real-time systems to an engineering journal. But the referees generally agreed my task model is too limited. My task model is a frame-based real-time application where all the tasks in the application have a common deadline D and are independent from each other. In the following Figure you can see a model of this application. enter image description here

The tasks T1 to T5 are independent from each other and have common deadline D.

"Independent" means that order of the tasks execution is flexible (is not important) or the tasks can be executed concurrently.

There are related works that have considered this type of real-time application, but none of these works include any real-world examples. The referees said that to convince the readers I must provide some real-world examples of this kind of application.

Does anybody know a real-world example for this kind of real-time application?

Raphael
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1 Answers1

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Example 1: Playing a multimedia stream where Task 1 must decompress an audio "frame" while Task 2 must decompress a video frame by the same deadline: the playback time for a given video frame.

This is a little unrealistic though because in practice there's a demux task that task 1 and 2 both depend on, and usually the audio and video playback frames have different repeating deadline frequencies.

Example 2: A robot might run all its control loops with the same frequency for simplicity. The control loops all depend on receiving a new set of sensor input values, then they all run, and they all send outputs to the actuators. E.g. Task 1 controls the motor for the left side of the tank drive, Task 2 controls the motor for the right side of the tank drive, while Task 3 controls the robot arm. It just simplifies things a bit to give all the control loops the same deadline unless there are interdependencies such as needing to mux the actuator control data into a single packet to send over a network to the actuators. In that case, a Mux task depends on all the control loop tasks.

Jerry101
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