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Task-Based Constant Bandwidth Server in the Zephyr Operating System

Authors Alexander Paschoaletto, Paulo Baltarejo Sousa , Luis Miguel Pinho , Tiago Carvalho

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OASIcs.AEiC.2026.6.pdf
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Subject Classification

ACM Subject Classification
  • Computer systems organization → Real-time operating systems
  • Theory of computation → Concurrent algorithms
Keywords
  • Constant Bandwidth Server
  • Zephyr Operating System

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Abstract

The Constant Bandwidth Server (CBS) is a widely used method to support aperiodic soft real-time tasks in a system that uses dynamic scheduling algorithms, such as Earliest Deadline First (EDF), while providing end-to-end temporal guarantees through bandwidth reservation. We have recently proposed an approach to integrate CBS with the open-source real-time operating system, Zephyr, which involves developing CBS as a separate kernel component that can be shared by multiple execution contexts. In this paper, we propose an alternative approach, which provides each task with a dedicated CBS instance, which enables fine-grained control over task execution. The paper also presents a richer support for EDF scheduling in Zephyr, which is used to support the Task-Based CBS. The proposed method is validated through test cases, demonstrating its efficiency in supporting aperiodic real-time tasks with bandwidth constraints in Zephyr.

Cite As Get BibTex

Alexander Paschoaletto, Paulo Baltarejo Sousa, Luis Miguel Pinho, and Tiago Carvalho. Task-Based Constant Bandwidth Server in the Zephyr Operating System. In 30th Ada-Europe International Conference on Reliable Software Technologies (AEiC 2026). Open Access Series in Informatics (OASIcs), Volume 143, pp. 6:1-6:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2026) https://doi.org/10.4230/OASIcs.AEiC.2026.6

Author Details

Alexander Paschoaletto
  • SoftCPS/ISEP, Porto, Portugal
Paulo Baltarejo Sousa
  • SoftCPS/ISEP & INESC TEC, Porto, Portugal
Luis Miguel Pinho
  • SoftCPS/ISEP & INESC TEC, Porto, Portugal
Tiago Carvalho
  • SoftCPS/ISEP & INESC TEC, Porto, Portugal

Funding

The work is co-funded by the Portuguese Innovation Agency (ANI) through the COMPETE 2030 and NORTE 2030 Programmes, with the support of the European Regional Development Fund (ERDF), within projects GenerIoT (COMPETE2030-FEDER-00355700) and HomePot (NORTE2030-FEDER-01241500).

Acknowledgements

The authors would like to thank the anonymous reviewers for their helpful comments and feedback.

References

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