A Survey from Real-Time to Near Real-Time Applications in Fog Computing Environments

In this article, we present a comprehensive survey on time-sensitive applications implemented in fog computing environments. The goal is to research what applications are being implemented in fog computing architectures and how the temporal requirements of these applications are being addressed. We also carried out a comprehensive analysis of the articles surveyed and separate them into categories, according to a pattern found in them. Our research is important for the area of real-time systems since the concept of systems that respond in real time has presented various understandings and concepts. This variability of concept has been due to the growing requirements for fast data communication and processing. Therefore, we present different concepts of real-time and near real-time systems found in the literature and currently accepted by the academic-scientific community. Finally, we conduct an analytical discussion of the characteristics and proposal of articles.

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A comprehensive survey of industry practice in real-time systems

Real-Time Systems ◽

10.1007/s11241-021-09376-1 ◽

2021 ◽

Author(s):

Benny Akesson ◽

Mitra Nasri ◽

Geoffrey Nelissen ◽

Sebastian Altmeyer ◽

Robert I. Davis

Keyword(s):

Embedded Systems ◽

Real Time ◽

Survey Data ◽

Common Knowledge ◽

Academic Research ◽

Real Time Systems ◽

The Real ◽

Industry Practice ◽

Comprehensive Survey ◽

Time Systems

AbstractThis paper presents results and observations from a survey of 120 industry practitioners in the field of real-time embedded systems. The survey provides insights into the characteristics of the systems being developed today and identifies important trends for the future. It extends the results from the survey data to the broader population that it is representative of, and discusses significant differences between application domains. The survey aims to inform both academics and practitioners, helping to avoid divergence between industry practice and academic research. The value of this research is highlighted by a study showing that the aggregate findings of the survey are not common knowledge in the real-time systems community.

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Beyond the Traditional Analyses and Resource Management in Real-Time Systems

Special Topics in Information Technology - SpringerBriefs in Applied Sciences and Technology ◽

10.1007/978-3-030-85918-3_6 ◽

2022 ◽

pp. 67-77

Author(s):

Federico Reghenzani

Keyword(s):

Real Time ◽

Real Time Systems ◽

Formal Proofs ◽

Worst Case ◽

Worst Case Execution Time ◽

Quantitative Results ◽

Real Time Applications ◽

Hard Real Time ◽

Phd Thesis ◽

Time Systems

AbstractThe difficulties in estimating the Worst-Case Execution Time (WCET) of applications make the use of modern computing architectures limited in real-time systems. Critical embedded systems require the tasks of hard real-time applications to meet their deadlines, and formal proofs on the validity of this condition are usually required by certification authorities. In the last decade, researchers proposed the use of probabilistic measurement-based methods to estimate the WCET instead of traditional static methods. In this chapter, we summarize recent theoretical and quantitative results on the use of probabilistic approaches to estimate the WCET presented in the PhD thesis of the author, including possible exploitation scenarios, open challenges, and future directions.

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Energy Optimization of Mixed-Criticality Distributed Real-Time Embedded Systems

Journal of Circuits System and Computers ◽

10.1142/s0218126621500857 ◽

2020 ◽

pp. 2150085

Author(s):

Ruoxu Sun ◽

Jinyu Zhan ◽

Wei Jiang ◽

Qi Dong ◽

Yalan Ye

Keyword(s):

Real Time ◽

System Level ◽

Optimization Approach ◽

Real Time Systems ◽

Safety Requirements ◽

Static Scheduling ◽

Dynamic Voltage ◽

Real Time Applications ◽

Time Systems ◽

Mixed Criticality

In this paper, we propose a system-level optimization approach for mixed-criticality distributed real-time systems with safety and energy considerations. We firstly depict a mixed-criticality distributed task model for real-time applications, in which the safety of the system is influenced by dynamic voltage and frequency scaling (DVFS). Due to the huge complexity of solving the problem optimally, a heuristic algorithm is proposed to approach the system-level optimization through a quasi-static scheduling strategy. The experiments demonstrate the efficiency of the proposed approach, which can obtain energy consumption while guaranteeing the system safety requirements.

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Integration of Optimization Approach Based on Multiple Wordlength Operation Grouping in the AAA Methodology for Real-Time Systems

International Journal of Embedded and Real-Time Communication Systems ◽

10.4018/ijertcs.2014010103 ◽

2014 ◽

Vol 5 (1) ◽

pp. 37-60

Author(s):

Ahmed Ghazi Blaiech ◽

Khaled Ben Khalifa ◽

Mohamed Boubaker ◽

Mohamed Akil ◽

Mohamed Hedi Bedoui

Keyword(s):

Neural Networks ◽

Real Time ◽

Vector Quantization ◽

Field Programmable Gate Array ◽

Optimization Approach ◽

Real Time Systems ◽

Reconfigurable Circuits ◽

Field Programmable ◽

Real Time Applications ◽

Time Systems

The Multiple-Wordlength Operation Grouping (MWOG) is a recently used approach for an optimized implementation on a Field Programmable Gate Array (FPGA). By fixing the precision constraint, this approach allows minimizing the data wordlength. In this paper, the authors present the integration of the approach based on the MWOG in the Algorithm Architecture Adequation (AAA) methodology, designed to implement real-time applications onto reconfigurable circuits. This new AAA-MWOG methodology will improve the optimization phase of the AAA methodology by taking into account the data wordlength and creating approximative-wordlength operation groups, where the operations in the same group will be performed with the same operator. The AAA-MWOG methodology will allow a considerable gain of circuit resources. This contribution is demonstrated by implementing the Learning Vector Quantization (LVQ) neural-networks model on the FPGA. The LVQ optimization is used to quantify vigilance states starting from processing the electroencephalographic signal. The precision-gain relation has been studied and reported.

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Predictable data communication interface for hard real-time systems

2008 International Workshop on Robotic and Sensors Environments ◽

10.1109/rose.2008.4669188 ◽

2008 ◽

Author(s):

Mihai V. Micea ◽

Gabriel N. Carstoiu ◽

Lucian Ungurean ◽

Dan Chiciudean ◽

Vladimir Cretu ◽

...

Keyword(s):

Real Time ◽

Data Communication ◽

Real Time Systems ◽

Communication Interface ◽

Hard Real Time ◽

Time Systems

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Using Fixed Priority Pre-emptive Scheduling in Real-Time Systems

International Journal of Computers Communications & Control ◽

10.15837/ijccc.2011.1.2213 ◽

2011 ◽

Vol 6 (1) ◽

pp. 187 ◽

Cited By ~ 2

Author(s):

Doina Zmaranda ◽

Gianina Gabor ◽

Daniela Elena Popescu ◽

Codruta Vancea ◽

Florin Vancea

Keyword(s):

Real Time ◽

Schedulability Analysis ◽

Scheduling Algorithms ◽

Real Time Systems ◽

Priority Scheduling ◽

Fixed Priority ◽

Fixed Priority Scheduling ◽

Rate Monotonic ◽

Real Time Applications ◽

Time Systems

For real-time applications, task scheduling is a problem of paramount importance. Several scheduling algorithms were proposed in the literature, starting from static scheduling or cyclic executives which provide very deterministic yet inflexible behaviour, to the so called best-effort scheduling, which facilitates maximum run-time flexibility but allows only probabilistic predictions of run-time performance presenting a non-predictable and nondeterministic solution. Between these two extremes lies fixed priority scheduling algorithms, such as Rate Monotonic, that is not so efficient for real-time purposes but exhibits a predictable approach because scheduling is doing offline and guarantees regarding process deadlines could be obtained using appropriate analysis methods. This paper investigates the use of Rate Monotonic algorithm by making adjustments in order to make it more suitable for real-time applications. The factors that motivate the interest for fixed priority scheduling algorithms such Rate Monotonic when doing with real-time systems lies in its associated analysis that could be oriented in two directions: schedulability analysis and analysis of process interactions. The analyzing process is carried out using a previously implemented framework that allows modelling, simulation and schedulability analysis for a set of real-time system tasks, and some of the results obtained are presented.

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