Coq à la conquête des moulins (original) (raw)
Algorithms for Parallel Processing
Springer eBooks, 1999
The copyright owner's consent does not include copying for general distribution, pro motion, new works, or resale. In these cases, specific wrilten permission must first be obtained from the publisher. Production managed by Alian Abrams; manufacturing supervised by Jeffrey Taub. Camera-ready copy prepared by the IMA.
Moscow ML Language Overview, Version 2.00 of June 2000
This is a compact reference to the language implemented by Moscow ML, a superset of Standard ML. For reference material on Standard ML, see Milner, Tofte, Harper and MacQueen: The Definition of Standard ML, The MIT Press 1997. For a guide to the practical use of Moscow ML, see the Moscow ML Owner’s Manual. For a detailed description of all Moscow ML library modules, see the Moscow ML Library Documentation.
Languages for Parallel Processing / Sprachen für die parallele Datenverarbeitung
it - Information Technology
Tom Lake studied Physics at Oxford and at the University of Pennsylvania, USA completing his doctorate in 1972. He started his computing career with the computing service of the University of London. He spent 8 years with the development branch of computer manufacturer ICL, where he was active in the design and production of its relational products and of the DAP FORTRAN system for ICL's 4096 processing element SIMD machine, the Distributed Array Processor (DAP). In 1985 he became a founding director of the parallel software company, Intercept Systems, and still has close involvement with software for the DAP. He is founding chair of the British Computer Society's Parallel Processing Specialist Group which has been a focus for those with a broad interest in parallel computing. The technical basis of computing is encouraging a shift to parallel architectures. Parallel computer languages and models of computation are examined. Four approaches to the provision of parallel languages are described taking as examples FOR-TRAN 77, SISAL, occam, FORTRAN 8X and CONCURRENT PROLOG. The impact of language developments on scientific and engineering computation is briefly discussed. Technische Gegebenheiten ermutigen zu einem Übergang auf parallele Architekturen. Parallele Computersprachen und Berechenbarkeitsmodelle (models of computation) werden untersucht. 4 Ansätze zur Erstellung von Parallel-Sprachen werden beschrieben, wobei als Beispiel FORTRAN 77, SI-SAL, occam, FORTRAN 8X und CONCURRENT PROLOG dienen. Der Einfluß der Entwicklung von Sprachen auf wissenschaftliche und technische Berechnungen werden kurz besprochen.
Stepwise Refinement of Parallel Algorithms
Science of Computer Programming, 1989
The refinement calculus and the action system formalism are combined to provide a uniform method for constructing parallel and distributed algorithms by stepwise refinement. It is shown that the sequential refinement calculus can be used as such for most of the derivation steps. Parallelism is introduced during the derivation by refinement of atomicity. The approach is applied to the derivation of a parallel version of the Gaussian elimination method for solving simultaneous linear equation systems. 0167-6423/90/503.50 0 1990-Elsevier Science Publishers B.V. (North-Holland)
Département de Mathématiques et Informatique
1998
Abstract Writing parallel programs is not easy, and debugging them is usually a nightmare. To cope with these difficulties, a structured approach to parallel programs using skeletons and template based compiler techniques has been developed over the past years by several researchers, including the P3L group in Pisa.
2017
In this thesis, a novel framework for paraUel processing is introduced. The main aim is to consider the modem processors architecture and to reduce the communication time among the processors of the paraUel environment. Several paraUel algorithms have been developed since more than four decades; aU of it takes the same mode of data decomposing and parallel processing. These algorithms suffer from the same drawbacks at different levels, which could be summarized that these algorithms consume too much time in communication among processors because of high data dependencies, on the other hand, communication time increases gradually as number of processors increases, also, as number of blocks of the decomposed data increases; sometime, communication time exceeds computation time in case of huge data to be parallel processed, which is the case of parallel matrix multiplication. On the other hand, all previous algorithms do not utilize the advances in the modem processors architecture. Matrices multiplication has been used as benchmark problem for aU parallel algorithms since it is one of the most fundamental numerical problem in science and engineering; starting by daily database transactions, meteorological forecasts, oceanography, astrophysics, fluid mechanics, nuclear engineering, chernical engineering, robotics and artificial intelligence, detection of petroleum and mineraIs, geological detection, medical research and the military, communication and telecommunication, analyzing DNA material, Simulating earthquakes, data mining and image processing. In this thesis, new parallel matrix multiplication algorithm has been developed under the novel framework which implies generating independent tasks among processors, to reduce the communication time among processors to zero and to utilize the modem processors architecture in term of the availability of the cache mem. The new algorithm utilized 97% of processing power in place, against maximum of 25% of processing power for previous algorithms. On the hand, new data decomposition technique has been developed for the problem where generating independent tasks is impossible, like solving Laplace equation, to reduce the communication cost. The new decomposition technique utilized 55% of processing power in place, against maximum of 30% of processing power for 2 Dimensions decomposition technique. v Foreword I dedicate this work frrst of aIl to my parents Hussein and Inaam, who partied the nights on my upbringing. I dedicate this work to my life partner and so my PhD partner .... Rana I foreword my work to the scientist of Math, to AI-K.hwarizmï, Abü Ja'far Muhammad Ibn Müsa, Pythagoras (IIu9U'yopaç), Isaac Newton, Archimedes, René Descartes, and Alan Mathison Turing, father of computer science. I foreword this work to my daughter Leen, and my sons Hussein, Yazan, and Muhammad. I would acknowledge proudly my supervisor Prof. Adel Omar Dahmane, for his unlimited support through my PhD march, and I would thank aIl who supported me by aIl means.
Languages and Compilers for Parallel Computing
Lecture Notes in Computer Science, 2000
all of the Computer Science and Engineering Department, for their excellent help. We also wish to acknowledge the great help of Chanathip Namprempre in editing and putting together this volume. We would like to give special thanks to the LCPC'99 program committee and the nameless external reviewers for their e orts in reviewing the submissions. Both the steering committee and the program committee helped with advice and suggestions on the organization of the workshop. Finally, we wish to thank all of the participants who helped to create a lively and constructive atmosphere of discussion, and the authors for sharing their signi cant research with us at LCPC '99.
2014
L'analyse et la compréhension du comportement d'applications parallèles sur des platesformes de calcul variées est un problème récurent de la communauté du calcul scientiőque. Lorsque les environnements d'exécution ne sont pas disponibles, la simulation devient une approche raisonnable pour obtenir des indicateurs de performance objectifs et pour explorer plusieurs scénarios łwhat-if?ž. Dans cette thèse, nous présentons un environnement pour la simulation of-line d'applications écrites avec MPI. La principale originalité de notre travail par rapport aux travaux précédents réside dans la déőnition de traces indépendantes du temps. Elles permettent d'obtenir une extensibilité maximale puisque des ressources hétérogènes et distribuées peuvent être utilisées pour obtenir une trace. Nous proposons un format dans lequel pour chaque événement qui apparaît durant l'exécution d'une application, nous récupérons les informations sur le volume d'instructions pour une phase de calcul ou le nombre d'octets et le type d'une communication. Pour obtenir des traces indépendantes du temps lors de l'exécution d'applications MPI, nous devons les instrumenter pour récupérer les données requises. Il existe plusieurs outils d'instrumentation qui peuvent instrumenter une application. Nous proposons un système de notation qui correspond aux besoins de notre environnement et nous évaluons les outils d'instrumentation selon lui. De plus, nous introduisons un outil original appelé Minimal Instrumentation qui a été conçu pour répondre au besoins de notre environnement. Nous étudions plusieurs méthodes d'instrumentation et plusieurs stratégies d'acquisition. Nous détaillons les outils qui extraient les traces indépendantes du temps à partir des traces d'instrumentations de quelques outils de proőling connus. Enőn nous évaluons la procédure d'acquisition complète et présentons l'acquisition d'instances à grande échelle. Nous décrivons en détail la procédure pour fournir un őchier de plateforme simulée réaliste à notre outil d'exécution de traces qui prend en compte la topologie de la plateforme cible ainsi que la procédure de calibrage par rapport à l'application qui va être simulée. De plus, nous montrons que notre simulateur peut prédire les performances de certains benchmarks MPI avec moins de 11% d'erreur relative entre l'exécution réelle et la simulation pour les cas où il n'y a pas de problème de performance. Enőn, nous identiőons les causes de problèmes de performances et nous proposons des solutions pour y remédier.