Distributed Simulation of Large-Scale Individual Oriented Models

The distributed simulation for high performance models has been carried-out into a very useful and low-cost tool. In the present work their application to an individual oriented model (Fish Schools) is analyzed. To do this, it was analyzed different alternatives for this type of simulation and their application to obtain performance and model scalability using different implementation. Thus, two distributed simulator have been developed based on PVM and MPI communication libraries. This paper resumes the advantages and drawbacks of each implementation and some conclusions about the distributed simulation for this type of models are extracted. Moreover, visualization aspects and the developed infrastructure based on OpenGl are described.Facultad de Informátic

Increasing the scalability and the speedup of a fish school distributed simulator

El present treball fa un anàlisi i desenvolupament sobre les millores en la velocitat i en l'escalabilitat d'un simulador distribuït de grups de peixos. Aquests resultats s'han obtingut fent servir una nova estratègia de comunicació per als processos lògics (LPs) i canvis en l'algoritme de selecció de veïns que s'aplica a cadascun dels peixos en cada pas de simulació. L'idea proposada permet que cada procés lògic anticipi futures necessitats de dades pels seus veïns reduint el temps de comunicació al limitar la quantitat de missatges intercanviats entre els LPs. El nou algoritme de selecció dels veïns es va desenvolupar amb l'objectiu d'evitar treball innecessari permetent la disminució de les instruccions executades en cada pas de simulació i per cadascun del peixos simulats reduint de forma significativa el temps de simulació.In this work we presented improvements in the speedup and scalability of a distributed fish school simulator. These results were achieved using a new communication strategy for logical processes (LPs) and changing the algorithm of neighbors selection that is applied to each fish in each simulation step. In the proposed approach each sender processes anticipates future data needs by its neighborhoods. That strategy reduces communication time by limiting the quantity of messages interchanged among LPs. The new neighbors selection algorithm was developed with the aim of avoiding unnecessary work. Diminishing the instructions executed by each fish been simulated in each simulation step helped to reduce a lot the simulation time

THE EVOLUTION OF ANNUAL MEAN TEMPERATURE AND PRECIPITATION QUANTITY VARIABILITY BASED ON ESTIMATED CHANGES BY THE REGIONAL CLIMATIC MODELS

Climatic changes are representing one of the major challenges of our century, these being forcasted according to climate scenarios and models, which represent plausible and concrete images of future climatic conditions. The results of climate models comparison regarding future water resources and temperature regime trend can become a useful instrument for decision makers in choosing the most effective decisions regarding economic, social and ecologic levels. The aim of this article is the analysis of temperature and pluviometric variability at the closest grid point to Cluj-Napoca, based on data provided by six different regional climate models (RCMs). Analysed on 30 year periods (2001-2030,2031-2060 and 2061-2090), the mean temperature has an ascending general trend, with great varability between periods. The precipitation expressed trough percentage deviation shows a descending general trend, which is more emphazied during 2031-2060 and 2061-2090

Heterogeneous CPU/GPU co-execution of CFD simulations on the POWER9 architecture: Application to airplane aerodynamics

High fidelity Computational Fluid Dynamics simulations are generally associated with large computing requirements, which are progressively acute with each new generation of supercomputers. However, significant research efforts are required to unlock the computing power of leading-edge systems, currently referred to as pre-Exascale systems, based on increasingly complex architectures. In this paper, we present the approach implemented in the computational mechanics code Alya. We describe in detail the parallelization strategy implemented to fully exploit the different levels of parallelism, together with a novel co-execution method for the efficient utilization of heterogeneous CPU/GPU architectures. The latter is based on a multi-code co-execution approach with a dynamic load balancing mechanism. The assessment of the performance of all the proposed strategies has been carried out for airplane simulations on the POWER9 architecture accelerated with NVIDIA Volta V100 GPUs

Distributed Simulation of Large-Scale Individual Oriented Models

The distributed simulation for high performance models has been carried-out into a very useful and low-cost tool. In the present work their application to an individual oriented model (Fish Schools) is analyzed. To do this, it was analyzed different alternatives for this type of simulation and their application to obtain performance and model scalability using different implementation. Thus, two distributed simulator have been developed based on PVM and MPI communication libraries. This paper resumes the advantages and drawbacks of each implementation and some conclusions about the distributed simulation for this type of models are extracted. Moreover, visualization aspects and the developed infrastructure based on OpenGl are described.Facultad de Informátic

Avaliação de clusters baseados em sistemas em um chip para a computação de alto desempenho: uma revisão

High-performance computing systems are the maximum expression in the field of processing for large amounts of data. However, their energy consumption is an aspect of great importance, which was not considered decades ago. Hence, software developers and hardware providers are obligated to approach new challenges to address energy consumption, and costs. Constructing a computational cluster with a large amount of systems on a chip can result in a powerful, ecologic platform, with the capacity to offer sufficient performance for different applications, as long as low costs and minimum energy consumption can be maintained. As a result, energy efficient hardware has an opportunity to impact upon the area of high-performance computing. This article presents a systematic review of the evaluations conducted on clusters of  ystems on a Chip for High-Performance computing in the research setting.Los sistemas de computación de alto desempeño son la máxima expresión en el campo de procesamiento para grandes cantidades de datos. Sin embargo, su consumo de energía es un aspecto de gran importancia que no era tenido en cuenta en décadas pasadas. Por lo tanto, desarrolladores de software y proveedores de hardware están obligados a enfocarse en nuevos retos para abordar el consumo de energía y costos. Construir un clúster informático con una gran cantidad de sistemas en un chip puede dar como resultado una plataforma poderosa, ecológica y capaz de ofrecer el rendimiento suficiente para diferentes aplicaciones, siempre y cuando se puedan mantener bajos costos y el menor consumo de energía posible. Como resultado, el hardware eficiente en el consumo de energía tiene la oportunidad de tener un impacto en el área de la computación de alto desempeño. En este artículo se presenta una revisión sistemática para conocer las evaluaciones realizadas a clústeres de sistemas en un chip para computación de alto desempeño en el ámbito investigativo. Os sistemas de computação de alto desempenho são a máxima expressão no campo de processamento para grandes quantidades de dados. No entanto, seu consumo de energia é um aspecto de grande importância que não era levado em consideração em décadas passadas. Portanto, desenvolvedores de software e provedores de hardware estão obrigados a focar-se em novos desafios para abordar o consumo de energia e  ustos. Construir um cluster informático com uma grande quantidade de sistemas em um chip pode dar como resultado uma plataforma poderosa, ecológica e capaz de oferecer o rendimento suficiente para diferentes aplicações, desde que possam ser mantidos baixos custos e o menor consumo de energia possível. Como resultado, o hardware eficiente no consumo de energia tem a oportunidade de ter um impacto na área da computação de alto desempenho. Neste artigo, apresenta-se uma revisão sistemática para conhecer as avaliações realizadas a clusters de sistemas em um chip para computação de alto desempenho no âmbito investigativo.&nbsp

Modelling and analyzing dredging and disposal activities using Telemac, Sisyphe and DredgeSim

Water Qualit

Simulación de modelos orientados al individuo

Los bancos de peces es un grupo social organizado sin la presencia de un líder. Esta organización se atribuye a dos patrones de comportamiento: atracción biosocial y orientación paralela. Este sistema puede modelarse mediante la aproximación del Modelo orientado al Individuo, donde la conducta de cada individuo por separado define el comportamiento grupal de todos los individuos. El objetivo del trabajo es mejorar el rendimiento del simulador mediante una programación híbrida que aproveche las alternativas de paralelismo en el cómputo que ofrecen las recientes arquitecturas multicore en sistemas de altas prestaciones.Els bancs de peixos és un grup social organitzat sense la presència d'un líder. Aquesta organització s'atribueix a dos patrons de comportament: atracció biosocial i orientació paral·lela. Aquest sistema pot modelar mitjançant l'aproximació del model orientat a l'individu, on la conducta de cada individu per separat defineix el comportament grupal de tots els individus. L'objectiu del treball és millorar el rendiment del simulador mitjançant una programació híbrida que aprofiti les alternatives de paral·lelisme en el còmput que ofereixen les recents arquitectures multicore en sistemes d'altes prestacions

Reanalysis in Earth System Science: Towards Terrestrial Ecosystem Reanalysis

A reanalysis is a physically consistent set of optimally merged simulated model states and historical observational data, using data assimilation. High computational costs for modelled processes and assimilation algorithms has led to Earth system specific reanalysis products for the atmosphere, the ocean and the land separately. Recent developments include the advanced uncertainty quantification and the generation of biogeochemical reanalysis for land and ocean. Here, we review atmospheric and oceanic reanalyses, and more in detail biogeochemical ocean and terrestrial reanalyses. In particular, we identify land surface, hydrologic and carbon cycle reanalyses which are nowadays produced in targeted projects for very specific purposes. Although a future joint reanalysis of land surface, hydrologic and carbon processes represents an analysis of important ecosystem variables, biotic ecosystem variables are assimilated only to a very limited extent. Continuous data sets of ecosystem variables are needed to explore biotic-abiotic interactions and the response of ecosystems to global change. Based on the review of existing achievements, we identify five major steps required to develop terrestrial ecosystem reanalysis to deliver continuous data streams on ecosystem dynamics

Desarrollo de aplicaciones paralelo/distribuidas orientadas a la predicción de incendios forestales

La problemática existente a raíz de la falta de exactitud presente en los parámetros de entrada en cualquier modelo científico o físico, puede producir consecuencias dramáticas en la salida del mismo si se trata éste de algún sistema crítico. Además, al citado problema deben sumarse las limitaciones impuestas por los propios modelos, las restricciones que agregan las soluciones numéricas y, por qué no, las provenientes de las propias implementaciones y versiones informáticas. Por tal motivo, resulta de gran interés el desarrollo de métodos y herramientas informáticos que se enfoquen en el tratamiento de la incertidumbre de los valores de entrada para lograr así una predicción lo más confiable posible por parte del modelo en cuestión. En el caso concreto de los incendios forestales, la simulación de la propagación constituye un desafío desde el punto de vista computacional, dada la complejidad que involucran los modelos, los métodos numéricos y la administración de los recursos. La clase de métodos que aborda nuestra línea de investigación constituye una importante herramienta para la prevención y predicción, dado que provee información acerca del posible comportamiento del fuego y las zonas que corren mayor peligro.Eje: Procesamiento Distribuido y ParaleloRed de Universidades con Carreras en Informática (RedUNCI