Optimizing Per-Core Priorities to Minimize End-To-End Latencies

Authors Francesco Paladino , Alessandro Biondi , Enrico Bini , Paolo Pazzaglia

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Francesco Paladino
  • Scuola Superiore Sant'Anna, Pisa, Italy
Alessandro Biondi
  • Scuola Superiore Sant'Anna, Pisa, Italy
Enrico Bini
  • University of Turin, Italy
Paolo Pazzaglia
  • Robert Bosch GmbH, Corporate Research, Renningen, Germany

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Francesco Paladino, Alessandro Biondi, Enrico Bini, and Paolo Pazzaglia. Optimizing Per-Core Priorities to Minimize End-To-End Latencies. In 36th Euromicro Conference on Real-Time Systems (ECRTS 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 298, pp. 6:1-6:25, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


Logical Execution Time (LET) allows decoupling the schedule of real-time periodic tasks from their communication, with the advantage of isolating the communication pattern from the variability of the schedule. However, when such tasks are organized in chains, the usage of LET at the task level does not necessarily transfer the same LET properties to the chain level. In this paper, we extend a LET-like model from tasks to chains spanning over multiple cores. We leverage the designed constant latency chains to optimize per-core priority assignment. Finally, we also provide a set of heuristic algorithms, that are compared in a large-scale experimental evaluation.

Subject Classification

ACM Subject Classification
  • Computer systems organization → Real-time systems
  • Computer systems organization → Embedded and cyber-physical systems
  • Software and its engineering → Multiprocessing / multiprogramming / multitasking
  • Software and its engineering → Real-time schedulability
  • Cause-Effect Chains
  • Logical Execution Time
  • End-to-End Latency
  • Design Optimization
  • Task Priorities
  • Data Age
  • Reaction Time


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