Scientific workflow orchestration interoperating HTC and HPC resources

8 páginas, 7 figuras.-- El Pdf del artículo es la versión pre-print.In this work we describe our developments towards the provision of a unified access method to different types of computing infrastructures at the interop- eration level. For that, we have developed a middleware suite which bridges not interoperable middleware stacks used for building distributed computing infrastructues, UNICORE and gLite. Our solution allows to transparently access and operate on HPC and HTC resources from a single interface. Using Kepler as workflow manager, we provide users with the needed integration of codes to create scientific workflows accessing both types of infrastructures.Peer reviewe

Scientific workflow orchestration interoperating HTC and HPC resources

8 páginas, 7 figuras.-- El Pdf del artículo es la versión pre-print.In this work we describe our developments towards the provision of a unified access method to different types of computing infrastructures at the interop- eration level. For that, we have developed a middleware suite which bridges not interoperable middleware stacks used for building distributed computing infrastructues, UNICORE and gLite. Our solution allows to transparently access and operate on HPC and HTC resources from a single interface. Using Kepler as workflow manager, we provide users with the needed integration of codes to create scientific workflows accessing both types of infrastructures.Peer reviewe

Modularity for Large Virtual Reality Applications

International audienceThis paper focuses on the design of high performance VR applications. These applications usually involve various I/O devices and complex simulations. A parallel architecture or grid infrastructure is required to provide the necessary I/O and processing capabilities. Developing such applications faces several difficulties, two important ones being software engineering and performance issues. We argue that application modularity is a key concept to help the developer handle the complexity of these applications. We discuss how various approaches borrowed from other existing works can be combined to significantly improve the modularity of VR applications. This led to the development of the FlowVR middleware that associates a data-flow model with a hierarchical component model. Different case studies are presented to discuss the benefits of the approach proposed

All in one Graphical Tool for the management of DIET a GridRPC Middleware

Also available as LIP Research Report 2008-24Grid Middleware are the link between large scale (and distributed) platforms and applications. Managing such a software system and the Grid environment itself can be a hard task when no dedicated (and integrated) tool exist. Some can be used through nice graphical interfaces, but they are usually dedicated to one or some limited tasks. They do not fulfill all the needs of a Grid end-user who wants to deploy Grid applications easily and rapidly. The aim of this paper is to present the case study of an all-in-one software system, designed for the management of a Grid Middleware and gathering user-friendly graphical interfaces answering to the various needs of end-users. Moreover the software system eases the use of the Grid by avoiding the scripting layer under a nice GUI enabling the user a faster and more efficient use of the Grid environment. By this means we demonstrate how the DietDashboard fulfills all the needs of a unified tool for Grid management. This paper gives a comparison with existing and well-known tools dedicated to some specific tasks such as Grid resources management, Grid monitoring, or Middleware management

Global Grids and Software Toolkits: A Study of Four Grid Middleware Technologies

Grid is an infrastructure that involves the integrated and collaborative use of computers, networks, databases and scientific instruments owned and managed by multiple organizations. Grid applications often involve large amounts of data and/or computing resources that require secure resource sharing across organizational boundaries. This makes Grid application management and deployment a complex undertaking. Grid middlewares provide users with seamless computing ability and uniform access to resources in the heterogeneous Grid environment. Several software toolkits and systems have been developed, most of which are results of academic research projects, all over the world. This chapter will focus on four of these middlewares--UNICORE, Globus, Legion and Gridbus. It also presents our implementation of a resource broker for UNICORE as this functionality was not supported in it. A comparison of these systems on the basis of the architecture, implementation model and several other features is included.Comment: 19 pages, 10 figure

Toward a Computational Steering Environment based on CORBA

International audienceThis paper presents the first step toward a computational steering environment based on CORBA. This environment, called EPSN, allows the control, the data exploration and the data modification for numerical simulations involving an iterative process. In order to be as generic as possible, we introduce an abstract model of steerable simulations. This abstraction allows us to build steering clients independently of a given simulation. This model is described with an XML syntax and is used in the simulation by some source code annotations. EPSN takes advantage of the CORBA technology to design a communication infrastructure with portability, interoperability and network transparency. In addition, the in-progress parallel CORBA objects will give us a very attractive framework for extending the steering to parallel and distributed simulations

DIET : new developments and recent results

Among existing grid middleware approaches, one simple, powerful, and flexibleapproach consists of using servers available in different administrative domainsthrough the classic client-server or Remote Procedure Call (RPC) paradigm.Network Enabled Servers (NES) implement this model also called GridRPC.Clients submit computation requests to a scheduler whose goal is to find aserver available on the grid. The aim of this paper is to give an overview of anNES middleware developed in the GRAAL team called DIET and to describerecent developments. DIET (Distributed Interactive Engineering Toolbox) is ahierarchical set of components used for the development of applications basedon computational servers on the grid.Parmi les intergiciels de grilles existants, une approche simple, flexible et performante consiste a utiliser des serveurs disponibles dans des domaines administratifs différents à travers le paradigme classique de l’appel de procédure àdistance (RPC). Les environnements de ce type, connus sous le terme de Network Enabled Servers, implémentent ce modèle appelé GridRPC. Des clientssoumettent des requêtes de calcul à un ordonnanceur dont le but consiste àtrouver un serveur disponible sur la grille.Le but de cet article est de donner un tour d’horizon d’un intergiciel développédans le projet GRAAL appelé DIET 1. DIET (Distributed Interactive Engineering Toolbox) est un ensemble hiérarchique de composants utilisés pour ledéveloppement d’applications basées sur des serveurs de calcul sur la grille

Vers le pilotage des simulations numériques sur la grille

National audienceLe projet EPSN a pour but de développer un environnement logiciel pour le pilotage de simulations numériques parallèles et distribuées. L'environnement EPSN permet d'instrumenter les simulations numériques et de construire des applications clientes, typiquement dédiées à la visualisation, capables de controler, d'extraire ou de modifier les données de la simulation a distance. Afin de mettre en oeuvre un couplage générique, nous avons introduit un modèle abstrait des simulations interactives reposant sur une description XML et une annotation du code source. Cette abstraction nous permet de développer des clients de pilotage indépendamment d'une simulation particulière. La couche de communication d'EPSN met a profit la technologie CORBA (portabilité́ , interopérabilité et transparence du réseau), tout en masquant aux utilisateurs finaux la complexité inhérente de cet intergiciel. Cet article présente le prototype séquentiel Epsilon ainsi que les premiers travaux autour des simulations parallèles SPMD