Shared Resource Contention in MCUs: A Reality Check and the Quest for Timeliness

Authors Daniel Oliveira , Weifan Chen , Sandro Pinto , Renato Mancuso

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Author Details

Daniel Oliveira
  • Centro ALGORITMI, University of Minho, Guimarães, Portugal
Weifan Chen
  • Department of Computer Science, Boston University, MA, USA
Sandro Pinto
  • Centro ALGORITMI, University of Minho, Guimarães, Portugal
Renato Mancuso
  • Department of Computer Science, Boston University, MA, USA


We would like to express our gratitude to the reviewers for their valuable feedback and suggestions.

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Daniel Oliveira, Weifan Chen, Sandro Pinto, and Renato Mancuso. Shared Resource Contention in MCUs: A Reality Check and the Quest for Timeliness. In 36th Euromicro Conference on Real-Time Systems (ECRTS 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 298, pp. 5:1-5:25, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


Microcontrollers (MCUs) are steadily embracing multi-core technology to meet growing performance demands. This trend marks a shift from their traditionally simple, deterministic designs to more complex and inherently less predictable architectures. While shared resource contention is well-studied in mid to high-end embedded systems, the emergence of multi-core architectures in MCUs introduces unique challenges and characteristics that existing research has not fully explored. In this paper, we conduct an in-depth investigation of both mainstream and next-generation MCU-based platforms, aiming to identify the sources of contention on systems typically lacking these problems. We empirically demonstrate substantial contention effects across different MCU architectures (i.e., from single- to multi-core configurations), highlighting significant application slowdowns. Notably, we observe that slowdowns can reach several orders of magnitude, with the most extreme cases showing up to a 3800x (times, not percent) increase in execution time. To address these issues, we propose and evaluate muTPArtc, a novel mechanism designed for Timely Progress Assessment (TPA) and TPA-based runtime control specifically tailored to MCUs. muTPArtc is an MCU-specialized TPA-based mechanism that leverages hardware facilities widely available in commercial off-the-shelf MCUs (i.e., hardware breakpoints and cycle counters) to successfully monitor applications' progress, detect, and mitigate timing violations. Our results demonstrate that muTPArtc effectively manages performance degradation due to interference, requiring only minimal modifications to the build pipeline and no changes to the source code of the target application, while incurring minor overheads.

Subject Classification

ACM Subject Classification
  • Computer systems organization → Real-time systems
  • multi-core microcontrollers
  • shared resources contention
  • progress-aware regulation


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