Maximizing the execution rate of low-criticality tasks in mixed criticality systems
نویسندگان
چکیده
Industrial fields must build at the most competitive price real-time systems made of an increasing number of functionalities. This can be achieved by hosting high-criticality tasks as well as consumer real-time low-criticality tasks on a same chip. The design of such Mixed-Criticality (MC) systems requires the use of an appropriate task model and a specific scheduling strategy. In this work, inspired by the existing elastic task model, we introduce stretching factors as a way for the low-criticality tasks to reduce their utilization, as well as a level of importance in order to define an order for applying these stretching factors. At run-time, the slack time generated by both the over-provisioned high-criticality and the low-criticality tasks is used to maximize the execution rate of the low-criticality tasks. We also show how to integrate this approach in the Time-Triggered paradigm (TT), in particular its impact on the data visibility principle between the low-criticality tasks when they have been stretched.
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