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From Timing Budgets to WCETs: Robust SIL- and BSW-Aware Clustering and Allocation for Iterative Automotive Software Development

Authors Tobias Denzinger, Matthias Becker , Peter Ulbrich

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LIPIcs.ECRTS.2026.19.pdf
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Document Identifiers

Subject Classification

ACM Subject Classification
  • Computer systems organization → Real-time systems
  • Computer systems organization → Embedded software
  • Software and its engineering → Software safety
Keywords
  • cause-effect chains
  • end-to-end latency constraints
  • automotive software
  • SIL
  • ASIL
  • AUTOSAR BSW
  • WCET refinement
  • timing analysis

Metrics

Abstract

Automotive ECUs integrate thousands of AUTOSAR runnables, substantial Basic Software (BSW), and heterogeneous multicore hardware. In iterative software-defined vehicle development, engineers must repeatedly revisit designs while maintaining stable runnable clustering and core allocations, which are expensive structural decisions. Beyond timing, Safety Integrity Levels (SILs), BSW overheads, and per-core memory strongly constrain these decisions, yet are rarely modeled jointly. This paper addresses these challenges through a chain-based analysis model that treats SIL constraints and BSW costs as first-class citizens, as well as an integrated toolchain that constructs job-level data-age constraints, forms SIL-compliant clusters, synthesizes multirate tasks, and maps application and BSW tasks to heterogeneous multicore platforms while checking timing and memory feasibility.
A case study based on a real-world motion/drive controller from our industrial partner is described, which serves as the basis for our evaluation. The evaluations are conducted using synthetic systems that reflect the characteristics of the case study. Across 13,825 synthesized systems, SIL/BSW-aware clustering substantially reduces pessimism in analysis. In the industrial configuration, our approach yields a 7% decrease in utilization, demonstrating its practical value. A refinement study, which progressively replaces early budget assumptions with WCET samples, indicates that SIL/BSW-aware clustering preserves structural decisions better than less-informed variants under the same resampling setup.

Cite As Get BibTex

Tobias Denzinger, Matthias Becker, and Peter Ulbrich. From Timing Budgets to WCETs: Robust SIL- and BSW-Aware Clustering and Allocation for Iterative Automotive Software Development. In 38th European Conference on Real-Time Systems (ECRTS 2026). Leibniz International Proceedings in Informatics (LIPIcs), Volume 375, pp. 19:1-19:27, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2026) https://doi.org/10.4230/LIPIcs.ECRTS.2026.19

Author Details

Tobias Denzinger
  • CARIAD SE, Ingolstadt, Germany
Matthias Becker
  • KTH Royal Institute of Technology Stockholm, Sweden
Peter Ulbrich
  • Technische Universität Dortmund, Germany

Funding

  • Becker, Matthias: The work was partially supported by the Swedish Research Council (VR) under the project nr. 2023-04773, and by Sweden’s Innovation Agency via the NFFP8 project 2024-01267: PARTI.

Acknowledgements

We thank our industrial partners in the CARIAD SE, Germany, for its collaboration and constructive feedback, which improved the quality and practical relevance of this project. Generative AI tools were used to support language polishing and LaTeX formatting. The authors reviewed and edited all affected text and metadata and take full responsibility for the content.

Supplementary Materials

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