Closed Loop Controller for Multicore Real-Time Systems

  • Johannes Freitag
  • Sascha Uhrig
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10793)


In critical and hard real-time applications multicore processors are still not used very often. One of the reasons is the lack of timing predictability or the high Worst Case Execution Time (WCET) overestimation caused by the use of shared resources. Nevertheless, multicore processors can significantly increase system integration density also in critical and hard real-time applications.

We present a Closed Performance Control Loop that enables a stand-alone WCET estimation of a hard real-time application and execution on a multicore system concurrently to other applications. The advantage of our proposal is that it is transparent and non-intrusive to the critical application. Moreover, it is implemented as an external safety net and no additional software functionality on the multicore is required. The previously presented Fingerprinting approach to measure an application’s performance is used as sensor element, extended by a Pulse Width Modulated core thwarting technique and two different control algorithms are combined to a Closed Control Loop.


Embedded multicore systems Critical systems Safety net Real-time systems 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.AirbusMunichGermany

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