R-Codesign: Codesign Methodology for Real-Time Reconfigurable Embedded Systems Under Energy Constraints

IEEE Trans. Syst. Man Cybern, Syst.

et al. 2020

Self Cite

This paper deals with real-time scheduling of homogeneous multi-core platforms powered by a battery to be periodically recharged. A system is composed of reconfigurable real-time dependent and periodic tasks to be assigned to different cores interconnected by a network-on-chip (NoC). The system is subject to reconfigurations, which are automatic operations allowing the addition and/or removal of tasks as well as their exchanged messages on the NoC. Consequently, any reconfiguration can violate real-time and energy constraints on cores as well as the NoC when the energy is unavailable until the next recharge. A novel periodic task model based on elastic coefficients and a new scheduling strategy are proposed to compute useful temporal parameters allowing for tasks and messages to meet the related constraints while controlling the communication cost on the NoC. This strategy is compared with an ILP-based optimal solution, and a tool named OptimalMappingTasks is developed to run different simulations that prove the originality of the paper's contribution.

Section: Nomenclature πmentioning

confidence: 99%

Energy-Efficient Scheduling of Real-Time Tasks in Reconfigurable Homogeneous Multicore Platforms

Gammoudi

Benzina

IEEE Trans. Syst. Man Cybern, Syst.

et al. 2020

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“…is characterized by: CN i cores allowing the execution of tasks [36], a memory Mem i of size SZ i [113], and a battery Bttr i with a capacity Cap i [32], [114]. If we consider a renewable energy source to supply the energy storage, then the incoming power received by the different storage units is supposed a constant along time.…”

Section: A System Formalizationmentioning

confidence: 99%

“…When the system design is completely validated, the whole architecture is automatically implemented as reported in [30] by reducing redundancies in different configurations or by improving the performance of generated tasks. We perform the test of reconfigurable tasks as reported in [31] before going to the co-design of the hardware and software parts where a methodology named Rco-design is reported in [32]. This approach performs the feasibility analysis of the real-time tasks and messages under energy constraints as reported in [33]- [36].…”

mentioning

confidence: 99%

“…We describe the different published papers in the following sections for (i) Design and ROCL validation of reconfigurable discrete-event systems, (ii) Formal modeling and verification, (iii) Implementation and software test, (iv) Co-Design and real-time scheduling, (v) Deployment and hardware test ( Figure 2). The conducted research works composing this methodology are applied to different areas such as reconfigurable medical platforms [10], reconfigurable wireless sensor networks [21], [34], [40], adaptive controllers in smart grids [12] or in microgrids [8], reconfigurable middleware for RT-Linux [34], [42]- [44], reconfigurable MP-SoC architectures [32], [45], reconfigurable embedded controllers in automotive [46], reconfigurable automotive production lines [47], reconfigurable platoons [9], [37], reconfigurable production lines in manufacturing industry [48]- [50], adaptive embedded software in Android-based secured smartphones [13], reconfigurable test devices of reconfigurable embedded hardware [41], reconfigurable radar for traffic control [51], reconfigurable baggage handling systems in airports [52], reconfigurable controllers of irrigation systems [21].…”

mentioning

confidence: 99%

See 1 more Smart Citation

On Reconfiguration Theory of Discrete-Event Systems: From Initial Specification Until Final Deployment

Mosbahi

2019

IEEE Access

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This paper presents an overview on different research activities that we did in the recent decade for developing reconfigurable discrete-event systems (RDESs) from initial high-level specification according to user requirements until final low-level deployment in target hardware components. A reconfiguration is any run-time scenario that adapts the system's behavior to any evolution in the related environment by adding or removing services or also configuring their parameters, i.e., their frequency, execution time, or also their location in the considered hardware architecture. Since the development of distributed RDESs under functional and extra-functional constraints is required by experts, we propose a complete methodology that deals first with their initial design with a new general profile named R-UML extending unified modeling language (UML) or also with new specific technology-oriented profiles, the validation of the related models with a new language R-OCL extending object constraint language (OCL), before their transformation to formal formalisms, such as Petri nets, timed automata, or B method for simulation or also formal verification of different properties. The checked models are transformed into OS reconfigurable tasks in the operational level, before applying a co-design methodology under functional, real-time, memory, and energy constraints for minimizing redundancies in tasks and for optimizing the composition of software and hardware parts together. We describe technology-oriented solutions for the scheduling of distributed RDESs by parameterizing tasks and their exchanged messages between multi-speed networked processors. We finish with the real low-level deployment on target hardware devices before applying useful software and hardware tests for checking the delivered system quality. These contributions, published in different journal and conference papers, are applied to different applications in medicine, wireless sensor networks, transportation systems, manufacturing industry, smart grids and microgrids, embedded technologies, and so on. We find significant gains in terms of the system reactivity and flexibility under related constraints. INDEX TERMS Discrete-event system, modeling and verification, design and validation, implementation and scheduling, real-time and energy aware scheduling, test and simulation, co-design and deployment, application. I. INTRODUCTION Automatic flexibility becomes a required criterion for dynamic system adaptability to any possible evolution in related environment. A reconfigurable system is considered in this paper as a discrete-event system (RDES) that adapts its behavior to recover faults or also improve required performance at run-time. It is a set of wired/wireless networked devices that run independent/dependent control software tasks exchanging messages on the network [1], [2]. These tasks and consequently the related messages should be executed under functional, memory, real-time, and energy constraints described in user requirements [3]-[5]. A reconfi...

“…Despite the huge number of the proposed protocols in literature, real-time communication (Khalgui et al, 2005), energy consumption (Ghribi et al, 2018) and congestion control remain one of the research challenges in LLNs (Khalgui et al, 2007) (Ramdani. et al, 2019) (Ramdani et al, 2018), where, i) realtime communication is subjected to packet loss, interference, unreliable data, missing deadline, particularly, for environmental monitoring applications that require reliable network performance and provide data timely and reliably (Wang et al, 2018) (Qin et al, 2012) (Khalgui et al, 2019), ii) energy consumption depends on many operations like communication, processing, etc, which increases when these operations increase, such in IoT the most of devices are battery operated, thus the energy consumption will be the network dominator (Wang et al, 2018), and iii) congestion occurs when the traffic load exceeds the available link capacity, buffet node capacity, contiguous or cascading failures, or the need of multihop forwarding (Al-Kashoash et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

QCOF: New RPL Extension for QoS and Congestion-Aware in Low Power and Lossy Network

Aissa

Grichi

Proceedings of the 14th International Conference on Software Technologies

et al. 2019

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Low power and lossy networks (LLNs) require a routing protocol under real-time and energy constraints, congestion aware and packet priority. Thus, Routing Protocol for Low power and lossy network (RPL) is recommended by Internet Engineering Task force (IETF) for LLN applications. In RPL, nodes select their optimal paths towards their preferred parents after meeting routing metrics that are injected in the objective function (OF). However, RPL did not impose any routing metric and left it open for implementation. In this paper, we propose a new RPL objective function which is based on the quality of service (QoS) and congestion-aware. In the case paths fail, we define new RPL control messages for enriching the network by adding more routing nodes. Extensive simulations show that QCOF achieves significant improvement in comparison with the existing objective functions, and appropriately satisfies real-time applications under QoS and network congestion.