345 research outputs found

    3rd Many-core Applications Research Community (MARC) Symposium. (KIT Scientific Reports ; 7598)

    Get PDF
    This manuscript includes recent scientific work regarding the Intel Single Chip Cloud computer and describes approaches for novel approaches for programming and run-time organization

    Run-time management for future MPSoC platforms

    Get PDF
    In recent years, we are witnessing the dawning of the Multi-Processor Systemon- Chip (MPSoC) era. In essence, this era is triggered by the need to handle more complex applications, while reducing overall cost of embedded (handheld) devices. This cost will mainly be determined by the cost of the hardware platform and the cost of designing applications for that platform. The cost of a hardware platform will partly depend on its production volume. In turn, this means that ??exible, (easily) programmable multi-purpose platforms will exhibit a lower cost. A multi-purpose platform not only requires ??exibility, but should also combine a high performance with a low power consumption. To this end, MPSoC devices integrate computer architectural properties of various computing domains. Just like large-scale parallel and distributed systems, they contain multiple heterogeneous processing elements interconnected by a scalable, network-like structure. This helps in achieving scalable high performance. As in most mobile or portable embedded systems, there is a need for low-power operation and real-time behavior. The cost of designing applications is equally important. Indeed, the actual value of future MPSoC devices is not contained within the embedded multiprocessor IC, but in their capability to provide the user of the device with an amount of services or experiences. So from an application viewpoint, MPSoCs are designed to ef??ciently process multimedia content in applications like video players, video conferencing, 3D gaming, augmented reality, etc. Such applications typically require a lot of processing power and a signi??cant amount of memory. To keep up with ever evolving user needs and with new application standards appearing at a fast pace, MPSoC platforms need to be be easily programmable. Application scalability, i.e. the ability to use just enough platform resources according to the user requirements and with respect to the device capabilities is also an important factor. Hence scalability, ??exibility, real-time behavior, a high performance, a low power consumption and, ??nally, programmability are key components in realizing the success of MPSoC platforms. The run-time manager is logically located between the application layer en the platform layer. It has a crucial role in realizing these MPSoC requirements. As it abstracts the platform hardware, it improves platform programmability. By deciding on resource assignment at run-time and based on the performance requirements of the user, the needs of the application and the capabilities of the platform, it contributes to ??exibility, scalability and to low power operation. As it has an arbiter function between different applications, it enables real-time behavior. This thesis details the key components of such an MPSoC run-time manager and provides a proof-of-concept implementation. These key components include application quality management algorithms linked to MPSoC resource management mechanisms and policies, adapted to the provided MPSoC platform services. First, we describe the role, the responsibilities and the boundary conditions of an MPSoC run-time manager in a generic way. This includes a de??nition of the multiprocessor run-time management design space, a description of the run-time manager design trade-offs and a brief discussion on how these trade-offs affect the key MPSoC requirements. This design space de??nition and the trade-offs are illustrated based on ongoing research and on existing commercial and academic multiprocessor run-time management solutions. Consequently, we introduce a fast and ef??cient resource allocation heuristic that considers FPGA fabric properties such as fragmentation. In addition, this thesis introduces a novel task assignment algorithm for handling soft IP cores denoted as hierarchical con??guration. Hierarchical con??guration managed by the run-time manager enables easier application design and increases the run-time spatial mapping freedom. In turn, this improves the performance of the resource assignment algorithm. Furthermore, we introduce run-time task migration components. We detail a new run-time task migration policy closely coupled to the run-time resource assignment algorithm. In addition to detailing a design-environment supported mechanism that enables moving tasks between an ISP and ??ne-grained recon??gurable hardware, we also propose two novel task migration mechanisms tailored to the Network-on-Chip environment. Finally, we propose a novel mechanism for task migration initiation, based on reusing debug registers in modern embedded microprocessors. We propose a reactive on-chip communication management mechanism. We show that by exploiting an injection rate control mechanism it is possible to provide a communication management system capable of providing a soft (reactive) QoS in a NoC. We introduce a novel, platform independent run-time algorithm to perform quality management, i.e. to select an application quality operating point at run-time based on the user requirements and the available platform resources, as reported by the resource manager. This contribution also proposes a novel way to manage the interaction between the quality manager and the resource manager. In order to have a the realistic, reproducible and ??exible run-time manager testbench with respect to applications with multiple quality levels and implementation tradev offs, we have created an input data generation tool denoted Pareto Surfaces For Free (PSFF). The the PSFF tool is, to the best of our knowledge, the ??rst tool that generates multiple realistic application operating points either based on pro??ling information of a real-life application or based on a designer-controlled random generator. Finally, we provide a proof-of-concept demonstrator that combines these concepts and shows how these mechanisms and policies can operate for real-life situations. In addition, we show that the proposed solutions can be integrated into existing platform operating systems

    Parallel and Distributed Computing

    Get PDF
    The 14 chapters presented in this book cover a wide variety of representative works ranging from hardware design to application development. Particularly, the topics that are addressed are programmable and reconfigurable devices and systems, dependability of GPUs (General Purpose Units), network topologies, cache coherence protocols, resource allocation, scheduling algorithms, peertopeer networks, largescale network simulation, and parallel routines and algorithms. In this way, the articles included in this book constitute an excellent reference for engineers and researchers who have particular interests in each of these topics in parallel and distributed computing

    Resource-aware Programming in a High-level Language - Improved performance with manageable effort on clustered MPSoCs

    Get PDF
    Bis 2001 bedeutete Moores und Dennards Gesetz eine Verdoppelung der Ausführungszeit alle 18 Monate durch verbesserte CPUs. Heute ist Nebenläufigkeit das dominante Mittel zur Beschleunigung von Supercomputern bis zu mobilen Geräten. Allerdings behindern neuere Phänomene wie "Dark Silicon" zunehmend eine weitere Beschleunigung durch Hardware. Um weitere Beschleunigung zu erreichen muss sich auch die Soft­ware mehr ihrer Hardware Resourcen gewahr werden. Verbunden mit diesem Phänomen ist eine immer heterogenere Hardware. Supercomputer integrieren Beschleuniger wie GPUs. Mobile SoCs (bspw. Smartphones) integrieren immer mehr Fähigkeiten. Spezialhardware auszunutzen ist eine bekannte Methode, um den Energieverbrauch zu senken, was ein weiterer wichtiger Aspekt ist, welcher mit der reinen Geschwindigkeit abgewogen werde muss. Zum Beispiel werden Supercomputer auch nach "Performance pro Watt" bewertet. Zur Zeit sind systemnahe low-level Programmierer es gewohnt über Hardware nachzudenken, während der gemeine high-level Programmierer es vorzieht von der Plattform möglichst zu abstrahieren (bspw. Cloud). "High-level" bedeutet nicht, dass Hardware irrelevant ist, sondern dass sie abstrahiert werden kann. Falls Sie eine Java-Anwendung für Android entwickeln, kann der Akku ein wichtiger Aspekt sein. Irgendwann müssen aber auch Hochsprachen resourcengewahr werden, um Geschwindigkeit oder Energieverbrauch zu verbessern. Innerhalb des Transregio "Invasive Computing" habe ich an diesen Problemen gearbeitet. In meiner Dissertation stelle ich ein Framework vor, mit dem man Hochsprachenanwendungen resourcengewahr machen kann, um so die Leistung zu verbessern. Das könnte beispielsweise erhöhte Effizienz oder schnellerer Ausführung für das System als Ganzes bringen. Ein Kerngedanke dabei ist, dass Anwendungen sich nicht selbst optimieren. Stattdessen geben sie alle Informationen an das Betriebssystem. Das Betriebssystem hat eine globale Sicht und trifft Entscheidungen über die Resourcen. Diesen Prozess nennen wir "Invasion". Die Aufgabe der Anwendung ist es, sich an diese Entscheidungen anzupassen, aber nicht selbst welche zu fällen. Die Herausforderung besteht darin eine Sprache zu definieren, mit der Anwendungen Resourcenbedingungen und Leistungsinformationen kommunizieren. So eine Sprache muss ausdrucksstark genug für komplexe Informationen, erweiterbar für neue Resourcentypen, und angenehm für den Programmierer sein. Die zentralen Beiträge dieser Dissertation sind: Ein theoretisches Modell der Resourcen-Verwaltung, um die Essenz des resourcengewahren Frameworks zu beschreiben, die Korrektheit der Entscheidungen des Betriebssystems bezüglich der Bedingungen einer Anwendung zu begründen und zum Beweis meiner Thesen von Effizienz und Beschleunigung in der Theorie. Ein Framework und eine Übersetzungspfad resourcengewahrer Programmierung für die Hochsprache X10. Zur Bewertung des Ansatzes haben wir Anwendungen aus dem High Performance Computing implementiert. Eine Beschleunigung von 5x konnte gemessen werden. Ein Speicherkonsistenzmodell für die X10 Programmiersprache, da dies ein notwendiger Schritt zu einer formalen Semantik ist, die das theoretische Modell und die konkrete Implementierung verknüpft. Zusammengefasst zeige ich, dass resourcengewahre Programmierung in Hoch\-sprachen auf zukünftigen Architekturen mit vielen Kernen mit vertretbarem Aufwand machbar ist und die Leistung verbessert

    Exploiting Hardware Abstraction for Parallel Programming Framework: Platform and Multitasking

    Get PDF
    With the help of the parallelism provided by the fine-grained architecture, hardware accelerators on Field Programmable Gate Arrays (FPGAs) can significantly improve the performance of many applications. However, designers are required to have excellent hardware programming skills and unique optimization techniques to explore the potential of FPGA resources fully. Intermediate frameworks above hardware circuits are proposed to improve either performance or productivity by leveraging parallel programming models beyond the multi-core era. In this work, we propose the PolyPC (Polymorphic Parallel Computing) framework, which targets enhancing productivity without losing performance. It helps designers develop parallelized applications and implement them on FPGAs. The PolyPC framework implements a custom hardware platform, on which programs written in an OpenCL-like programming model can launch. Additionally, the PolyPC framework extends vendor-provided tools to provide a complete development environment including intermediate software framework, and automatic system builders. Designers\u27 programs can be either synthesized as hardware processing elements (PEs) or compiled to executable files running on software PEs. Benefiting from nontrivial features of re-loadable PEs, and independent group-level schedulers, the multitasking is enabled for both software and hardware PEs to improve the efficiency of utilizing hardware resources. The PolyPC framework is evaluated regarding performance, area efficiency, and multitasking. The results show a maximum 66 times speedup over a dual-core ARM processor and 1043 times speedup over a high-performance MicroBlaze with 125 times of area efficiency. It delivers a significant improvement in response time to high-priority tasks with the priority-aware scheduling. Overheads of multitasking are evaluated to analyze trade-offs. With the help of the design flow, the OpenCL application programs are converted into executables through the front-end source-to-source transformation and back-end synthesis/compilation to run on PEs, and the framework is generated from users\u27 specifications

    Embedded System Design

    Get PDF
    A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues

    On Energy Efficient Computing Platforms

    Get PDF
    In accordance with the Moore's law, the increasing number of on-chip integrated transistors has enabled modern computing platforms with not only higher processing power but also more affordable prices. As a result, these platforms, including portable devices, work stations and data centres, are becoming an inevitable part of the human society. However, with the demand for portability and raising cost of power, energy efficiency has emerged to be a major concern for modern computing platforms. As the complexity of on-chip systems increases, Network-on-Chip (NoC) has been proved as an efficient communication architecture which can further improve system performances and scalability while reducing the design cost. Therefore, in this thesis, we study and propose energy optimization approaches based on NoC architecture, with special focuses on the following aspects. As the architectural trend of future computing platforms, 3D systems have many bene ts including higher integration density, smaller footprint, heterogeneous integration, etc. Moreover, 3D technology can signi cantly improve the network communication and effectively avoid long wirings, and therefore, provide higher system performance and energy efficiency. With the dynamic nature of on-chip communication in large scale NoC based systems, run-time system optimization is of crucial importance in order to achieve higher system reliability and essentially energy efficiency. In this thesis, we propose an agent based system design approach where agents are on-chip components which monitor and control system parameters such as supply voltage, operating frequency, etc. With this approach, we have analysed the implementation alternatives for dynamic voltage and frequency scaling and power gating techniques at different granularity, which reduce both dynamic and leakage energy consumption. Topologies, being one of the key factors for NoCs, are also explored for energy saving purpose. A Honeycomb NoC architecture is proposed in this thesis with turn-model based deadlock-free routing algorithms. Our analysis and simulation based evaluation show that Honeycomb NoCs outperform their Mesh based counterparts in terms of network cost, system performance as well as energy efficiency.Siirretty Doriast

    Broadcast-oriented wireless network-on-chip : fundamentals and feasibility

    Get PDF
    Premi extraordinari doctorat UPC curs 2015-2016, àmbit Enginyeria de les TICRecent years have seen the emergence and ubiquitous adoption of Chip Multiprocessors (CMPs), which rely on the coordinated operation of multiple execution units or cores. Successive CMP generations integrate a larger number of cores seeking higher performance with a reasonable cost envelope. For this trend to continue, however, important scalability issues need to be solved at different levels of design. Scaling the interconnect fabric is a grand challenge by itself, as new Network-on-Chip (NoC) proposals need to overcome the performance hurdles found when dealing with the increasingly variable and heterogeneous communication demands of manycore processors. Fast and flexible NoC solutions are needed to prevent communication become a performance bottleneck, situation that would severely limit the design space at the architectural level and eventually lead to the use of software frameworks that are slow, inefficient, or less programmable. The emergence of novel interconnect technologies has opened the door to a plethora of new NoCs promising greater scalability and architectural flexibility. In particular, wireless on-chip communication has garnered considerable attention due to its inherent broadcast capabilities, low latency, and system-level simplicity. Most of the resulting Wireless Network-on-Chip (WNoC) proposals have set the focus on leveraging the latency advantage of this paradigm by creating multiple wireless channels to interconnect far-apart cores. This strategy is effective as the complement of wired NoCs at moderate scales, but is likely to be overshadowed at larger scales by technologies such as nanophotonics unless bandwidth is unrealistically improved. This dissertation presents the concept of Broadcast-Oriented Wireless Network-on-Chip (BoWNoC), a new approach that attempts to foster the inherent simplicity, flexibility, and broadcast capabilities of the wireless technology by integrating one on-chip antenna and transceiver per processor core. This paradigm is part of a broader hybrid vision where the BoWNoC serves latency-critical and broadcast traffic, tightly coupled to a wired plane oriented to large flows of data. By virtue of its scalable broadcast support, BoWNoC may become the key enabler of a wealth of unconventional hardware architectures and algorithmic approaches, eventually leading to a significant improvement of the performance, energy efficiency, scalability and programmability of manycore chips. The present work aims not only to lay the fundamentals of the BoWNoC paradigm, but also to demonstrate its viability from the electronic implementation, network design, and multiprocessor architecture perspectives. An exploration at the physical level of design validates the feasibility of the approach at millimeter-wave bands in the short term, and then suggests the use of graphene-based antennas in the terahertz band in the long term. At the link level, this thesis provides an insightful context analysis that is used, afterwards, to drive the design of a lightweight protocol that reliably serves broadcast traffic with substantial latency improvements over state-of-the-art NoCs. At the network level, our hybrid vision is evaluated putting emphasis on the flexibility provided at the network interface level, showing outstanding speedups for a wide set of traffic patterns. At the architecture level, the potential impact of the BoWNoC paradigm on the design of manycore chips is not only qualitatively discussed in general, but also quantitatively assessed in a particular architecture for fast synchronization. Results demonstrate that the impact of BoWNoC can go beyond simply improving the network performance, thereby representing a possible game changer in the manycore era.Avenços en el disseny de multiprocessadors han portat a una àmplia adopció dels Chip Multiprocessors (CMPs), que basen el seu potencial en la operació coordinada de múltiples nuclis de procés. Generacions successives han anat integrant més nuclis en la recerca d'alt rendiment amb un cost raonable. Per a que aquesta tendència continuï, però, cal resoldre importants problemes d'escalabilitat a diferents capes de disseny. Escalar la xarxa d'interconnexió és un gran repte en ell mateix, ja que les noves propostes de Networks-on-Chip (NoC) han de servir un tràfic eminentment variable i heterogeni dels processadors amb molts nuclis. Són necessàries solucions ràpides i flexibles per evitar que les comunicacions dins del xip es converteixin en el pròxim coll d'ampolla de rendiment, situació que limitaria en gran mesura l'espai de disseny a nivell d'arquitectura i portaria a l'ús d'arquitectures i models de programació lents, ineficients o poc programables. L'aparició de noves tecnologies d'interconnexió ha possibilitat la creació de NoCs més flexibles i escalables. En particular, la comunicació intra-xip sense fils ha despertat un interès considerable en virtut de les seva baixa latència, simplicitat, i bon rendiment amb tràfic broadcast. La majoria de les Wireless NoC (WNoC) proposades fins ara s'han centrat en aprofitar l'avantatge en termes de latència d'aquest nou paradigma creant múltiples canals sense fils per interconnectar nuclis allunyats entre sí. Aquesta estratègia és efectiva per complementar a NoCs clàssiques en escales mitjanes, però és probable que altres tecnologies com la nanofotònica puguin jugar millor aquest paper a escales més grans. Aquesta tesi presenta el concepte de Broadcast-Oriented WNoC (BoWNoC), un nou enfoc que intenta rendibilitzar al màxim la inherent simplicitat, flexibilitat, i capacitats broadcast de la tecnologia sense fils integrant una antena i transmissor/receptor per cada nucli del processador. Aquest paradigma forma part d'una visió més àmplia on un BoWNoC serviria tràfic broadcast i urgent, mentre que una xarxa convencional serviria fluxos de dades més pesats. En virtut de la escalabilitat i del seu suport broadcast, BoWNoC podria convertir-se en un element clau en una gran varietat d'arquitectures i algoritmes poc convencionals que milloressin considerablement el rendiment, l'eficiència, l'escalabilitat i la programabilitat de processadors amb molts nuclis. El present treball té com a objectius no només estudiar els aspectes fonamentals del paradigma BoWNoC, sinó també demostrar la seva viabilitat des dels punts de vista de la implementació, i del disseny de xarxa i arquitectura. Una exploració a la capa física valida la viabilitat de l'enfoc usant tecnologies longituds d'ona milimètriques en un futur proper, i suggereix l'ús d'antenes de grafè a la banda dels terahertz ja a més llarg termini. A capa d'enllaç, la tesi aporta una anàlisi del context de l'aplicació que és, més tard, utilitzada per al disseny d'un protocol d'accés al medi que permet servir tràfic broadcast a baixa latència i de forma fiable. A capa de xarxa, la nostra visió híbrida és avaluada posant èmfasi en la flexibilitat que aporta el fet de prendre les decisions a nivell de la interfície de xarxa, mostrant grans millores de rendiment per una àmplia selecció de patrons de tràfic. A nivell d'arquitectura, l'impacte que el concepte de BoWNoC pot tenir sobre el disseny de processadors amb molts nuclis no només és debatut de forma qualitativa i genèrica, sinó també avaluat quantitativament per una arquitectura concreta enfocada a la sincronització. Els resultats demostren que l'impacte de BoWNoC pot anar més enllà d'una millora en termes de rendiment de xarxa; representant, possiblement, un canvi radical a l'era dels molts nuclisAward-winningPostprint (published version

    Multiprocessing techniques for unmanned multifunctional satellites Final report,

    Get PDF
    Simulation of on-board multiprocessor for long lived unmanned space satellite contro

    Broadcast-oriented wireless network-on-chip : fundamentals and feasibility

    Get PDF
    Premi extraordinari doctorat UPC curs 2015-2016, àmbit Enginyeria de les TICRecent years have seen the emergence and ubiquitous adoption of Chip Multiprocessors (CMPs), which rely on the coordinated operation of multiple execution units or cores. Successive CMP generations integrate a larger number of cores seeking higher performance with a reasonable cost envelope. For this trend to continue, however, important scalability issues need to be solved at different levels of design. Scaling the interconnect fabric is a grand challenge by itself, as new Network-on-Chip (NoC) proposals need to overcome the performance hurdles found when dealing with the increasingly variable and heterogeneous communication demands of manycore processors. Fast and flexible NoC solutions are needed to prevent communication become a performance bottleneck, situation that would severely limit the design space at the architectural level and eventually lead to the use of software frameworks that are slow, inefficient, or less programmable. The emergence of novel interconnect technologies has opened the door to a plethora of new NoCs promising greater scalability and architectural flexibility. In particular, wireless on-chip communication has garnered considerable attention due to its inherent broadcast capabilities, low latency, and system-level simplicity. Most of the resulting Wireless Network-on-Chip (WNoC) proposals have set the focus on leveraging the latency advantage of this paradigm by creating multiple wireless channels to interconnect far-apart cores. This strategy is effective as the complement of wired NoCs at moderate scales, but is likely to be overshadowed at larger scales by technologies such as nanophotonics unless bandwidth is unrealistically improved. This dissertation presents the concept of Broadcast-Oriented Wireless Network-on-Chip (BoWNoC), a new approach that attempts to foster the inherent simplicity, flexibility, and broadcast capabilities of the wireless technology by integrating one on-chip antenna and transceiver per processor core. This paradigm is part of a broader hybrid vision where the BoWNoC serves latency-critical and broadcast traffic, tightly coupled to a wired plane oriented to large flows of data. By virtue of its scalable broadcast support, BoWNoC may become the key enabler of a wealth of unconventional hardware architectures and algorithmic approaches, eventually leading to a significant improvement of the performance, energy efficiency, scalability and programmability of manycore chips. The present work aims not only to lay the fundamentals of the BoWNoC paradigm, but also to demonstrate its viability from the electronic implementation, network design, and multiprocessor architecture perspectives. An exploration at the physical level of design validates the feasibility of the approach at millimeter-wave bands in the short term, and then suggests the use of graphene-based antennas in the terahertz band in the long term. At the link level, this thesis provides an insightful context analysis that is used, afterwards, to drive the design of a lightweight protocol that reliably serves broadcast traffic with substantial latency improvements over state-of-the-art NoCs. At the network level, our hybrid vision is evaluated putting emphasis on the flexibility provided at the network interface level, showing outstanding speedups for a wide set of traffic patterns. At the architecture level, the potential impact of the BoWNoC paradigm on the design of manycore chips is not only qualitatively discussed in general, but also quantitatively assessed in a particular architecture for fast synchronization. Results demonstrate that the impact of BoWNoC can go beyond simply improving the network performance, thereby representing a possible game changer in the manycore era.Avenços en el disseny de multiprocessadors han portat a una àmplia adopció dels Chip Multiprocessors (CMPs), que basen el seu potencial en la operació coordinada de múltiples nuclis de procés. Generacions successives han anat integrant més nuclis en la recerca d'alt rendiment amb un cost raonable. Per a que aquesta tendència continuï, però, cal resoldre importants problemes d'escalabilitat a diferents capes de disseny. Escalar la xarxa d'interconnexió és un gran repte en ell mateix, ja que les noves propostes de Networks-on-Chip (NoC) han de servir un tràfic eminentment variable i heterogeni dels processadors amb molts nuclis. Són necessàries solucions ràpides i flexibles per evitar que les comunicacions dins del xip es converteixin en el pròxim coll d'ampolla de rendiment, situació que limitaria en gran mesura l'espai de disseny a nivell d'arquitectura i portaria a l'ús d'arquitectures i models de programació lents, ineficients o poc programables. L'aparició de noves tecnologies d'interconnexió ha possibilitat la creació de NoCs més flexibles i escalables. En particular, la comunicació intra-xip sense fils ha despertat un interès considerable en virtut de les seva baixa latència, simplicitat, i bon rendiment amb tràfic broadcast. La majoria de les Wireless NoC (WNoC) proposades fins ara s'han centrat en aprofitar l'avantatge en termes de latència d'aquest nou paradigma creant múltiples canals sense fils per interconnectar nuclis allunyats entre sí. Aquesta estratègia és efectiva per complementar a NoCs clàssiques en escales mitjanes, però és probable que altres tecnologies com la nanofotònica puguin jugar millor aquest paper a escales més grans. Aquesta tesi presenta el concepte de Broadcast-Oriented WNoC (BoWNoC), un nou enfoc que intenta rendibilitzar al màxim la inherent simplicitat, flexibilitat, i capacitats broadcast de la tecnologia sense fils integrant una antena i transmissor/receptor per cada nucli del processador. Aquest paradigma forma part d'una visió més àmplia on un BoWNoC serviria tràfic broadcast i urgent, mentre que una xarxa convencional serviria fluxos de dades més pesats. En virtut de la escalabilitat i del seu suport broadcast, BoWNoC podria convertir-se en un element clau en una gran varietat d'arquitectures i algoritmes poc convencionals que milloressin considerablement el rendiment, l'eficiència, l'escalabilitat i la programabilitat de processadors amb molts nuclis. El present treball té com a objectius no només estudiar els aspectes fonamentals del paradigma BoWNoC, sinó també demostrar la seva viabilitat des dels punts de vista de la implementació, i del disseny de xarxa i arquitectura. Una exploració a la capa física valida la viabilitat de l'enfoc usant tecnologies longituds d'ona milimètriques en un futur proper, i suggereix l'ús d'antenes de grafè a la banda dels terahertz ja a més llarg termini. A capa d'enllaç, la tesi aporta una anàlisi del context de l'aplicació que és, més tard, utilitzada per al disseny d'un protocol d'accés al medi que permet servir tràfic broadcast a baixa latència i de forma fiable. A capa de xarxa, la nostra visió híbrida és avaluada posant èmfasi en la flexibilitat que aporta el fet de prendre les decisions a nivell de la interfície de xarxa, mostrant grans millores de rendiment per una àmplia selecció de patrons de tràfic. A nivell d'arquitectura, l'impacte que el concepte de BoWNoC pot tenir sobre el disseny de processadors amb molts nuclis no només és debatut de forma qualitativa i genèrica, sinó també avaluat quantitativament per una arquitectura concreta enfocada a la sincronització. Els resultats demostren que l'impacte de BoWNoC pot anar més enllà d'una millora en termes de rendiment de xarxa; representant, possiblement, un canvi radical a l'era dels molts nuclisAward-winningPostprint (published version
    corecore