Estimation of Worst Case Response Time boundaries in multi-core real-time systems

AbstractWe investigate the mathematical properties of event bound functions as they are used in the worst-case response time analysis and utilization tests. We figure out the differences and similarities between the two approaches. Based on this analysis, we derive a more general form do describe events and event bounds. This new unified approach gives clear new insights in the investigation of real-time systems, simplifies the models and will support algebraic proofs in future work. In the end, we present a unified analysis which allows the algebraic definition of any scheduler. Introducing such functions to the real-time scheduling theory will lead two a more systematic way to integrate new concepts and applications to the theory. Last but not least, we show how the response time analysis in dynamic scheduling can be improved.

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Use of Measurements in Worst-Case Execution Time Estimation for Real-Time Systems

10.1109/sbesc53686.2021.9628230 ◽

2021 ◽

Author(s):

Jessica Junia Santillo Costa ◽

Romulo Silva de Oliveira ◽

Luis Fernando Arcaro

Keyword(s):

Real Time ◽

Execution Time ◽

Time Estimation ◽

Real Time Systems ◽

Worst Case ◽

Worst Case Execution Time ◽

Time Systems

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Best-case analysis for improving the worst-case schedulability test for distributed hard real-time systems

Proceeding. 10th EUROMICRO Workshop on Real-Time Systems (Cat. No.98EX168) ◽

10.1109/emwrts.1998.684945 ◽

2002 ◽

Cited By ~ 25

Author(s):

J.C. Palencia Gutierrez ◽

J.J. Gutierrez Garcia ◽

M. Gonzalez Harbour

Keyword(s):

Real Time ◽

Case Analysis ◽

Real Time Systems ◽

Worst Case ◽

Schedulability Test ◽

Hard Real Time ◽

Time Systems

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A Method for Simultaneously Satisfying Important Constraints and Dependencies for Many Different Types of Processes in Embedded Real-Time Systems

Volume 3: 2011 ASME/IEEE International Conference on Mechatronic and Embedded Systems and Applications, Parts A and B ◽

10.1115/detc2011-47928 ◽

2011 ◽

Author(s):

Jia Xu

Keyword(s):

Real Time ◽

Computation Time ◽

Real Time Systems ◽

Worst Case ◽

Release Times ◽

Different Types ◽

High Assurance ◽

Run Time ◽

Soft Deadline ◽

Time Systems

In most embedded, real-time applications, processes need to satisfy various important constraints and dependencies, such as release times, offsets, precedence relations, and exclusion relations. Embedded, real-time systems with high assurance requirements often must execute many different types of processes with such constraints and dependencies. Some of the processes may be periodic and some of them may be asynchronous. Some of the processes may have hard deadlines and some of them may have soft deadlines. For some of the processes, especially the hard real-time processes, complete knowledge about their characteristics can and must be acquired before run-time. For other processes, prior knowledge of their worst case computation time and their data requirements may not be available. It is important for many embedded real-time systems to be able to simultaneously satisfy as many important constraints and dependencies as possible for as many different types of processes as possible. In this paper, we discuss what types of important constraints and dependencies can be satisfied among what types of processes. We also present a method which guarantees that, for every process, no matter whether it is periodic or asynchronous, and no matter whether it has a hard deadline or a soft deadline, as long as the characteristics of that process are known before run-time, then that process will be guaranteed to be completed before predetermined time limits, while simultaneously satisfying many important constraints and dependencies with other processes.

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