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Programming Effort (programming + effort)

Distribution by Scientific Domains
Information Science and Computing60%
Engineering40%

Selected Abstracts

Performance comparison of MPI and OpenMP on shared memory multiprocessors

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 1 2006
Géraud Krawezik
Abstract When using a shared memory multiprocessor, the programmer faces the issue of selecting the portable programming model which will provide the best performance. Even if they restricts their choice to the standard programming environments (MPI and OpenMP), they have to select a programming approach among MPI and the variety of OpenMP programming styles. To help the programmer in their decision, we compare MPI with three OpenMP programming styles (loop level, loop level with large parallel sections, SPMD) using a subset of the NAS benchmark (CG, MG, FT, LU), two dataset sizes (A and B), and two shared memory multiprocessors (IBM SP3 NightHawk II, SGI Origin 3800). We have developed the first SPMD OpenMP version of the NAS benchmark and gathered other OpenMP versions from independent sources (PBN, SDSC and RWCP). Experimental results demonstrate that OpenMP provides competitive performance compared with MPI for a large set of experimental conditions. Not surprisingly, the two best OpenMP versions are those requiring the strongest programming effort. MPI still provides the best performance under some conditions. We present breakdowns of the execution times and measurements of hardware performance counters to explain the performance differences. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Workload decomposition strategies for hierarchical distributed-shared memory parallel systems and their implementation with integration of high-level parallel languages

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 11 2002
Sergio Briguglio
Abstract In this paper we address the issue of workload decomposition in programming hierarchical distributed-shared memory parallel systems. The workload decomposition we have devised consists of a two-stage procedure: a higher-level decomposition among the computational nodes; and a lower-level one among the processors of each computational node. By focusing on porting of a case study particle-in-cell application, we have implemented the described work decomposition without large programming effort by using and integrating the high-level language extensions High-Performance Fortran and OpenMP. Copyright © 2002 John Wiley & Sons, Ltd. [source]

On a multilevel preconditioning module for unstructured mesh Krylov solvers: two-level Schwarz

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 6 2002
R. S. Tuminaro
Abstract Multilevel methods offer the best promise to attain both fast convergence and parallel efficiency in the numerical solution of parabolic and elliptic partial differential equations. Unfortunately, they have not been widely used in part because of implementation difficulties for unstructured mesh solvers. To facilitate use, a multilevel preconditioner software module, ML, has been constructed. Several methods are provided requiring relatively modest programming effort on the part of the application developer. This report discusses the implementation of one method in the module: a two-level Krylov,Schwarz preconditioner. To illustrate the use of these methods in computational fluid dynamics (CFD) engineering applications, we present results for 2D and 3D CFD benchmark problems. Copyright © 2002 John Wiley & Sons, Ltd. [source]

UbiXML: programmable management of ubiquitous computing resources

INTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 6 2007
Dimitris Alexopoulos
XML technologies provide proven benefits for the configuration management of complex heterogeneous multi-vendor networks. These benefits have been recently manifested in numerous research, industrial and standardization efforts, including the XMLNET architecture. In this paper we present UbiXML, a system for programmable management of ubiquitous computing resources. UbiXML extends the benefits of XML technologies in the broader class of ubiquitous computing environments, which are inherently complex distributed heterogeneous and multi-vendor. In UbiXML management applications are structured as XML documents that incorporate programming constructs. Thus, UbiXML allows administrators to build sophisticated management applications with little or no programming effort. While UbiXML builds on several XMLNET concepts, it significantly augments XMLNET to handle management of sensors, perceptual components and actuating devices. Moreover, UbiXML is extensible towards additional ubiquitous computing elements. UbiXML has been exploited in implementing realistic management applications for a smart space. Copyright © 2007 John Wiley & Sons, Ltd. [source]

New centralized automatic vehicle location communications software system under GIS environment

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 9 2005
Omar Al-Bayari
Abstract Recent advances in wireless communications and networks have integrated relatively new technologies such as Global Positioning System (GPS), to the popular Global System for Mobile Communication (GSM), second generation cellular systems and the Geographic Information Systems (GIS) technologies. Automatic Vehicle Location (AVL) is based on a combination of GPS, GIS and telecommunication technologies. Automatic Vehicle Tracking systems are more and more used for different purposes, especially those related to tracking one vehicle or a fleet of vehicles. In this work, we introduce a new AVL system, which is based and developed under GIS software environment. The centralized software at the control station offers a new technology of transferring the intelligence of tracking system from the car unit, into the control office PC software. Centralized software will reduce the programming efforts in the car unit and will offer better fleet management. Moreover, the core of our system is based on the objects or the controllers of the GIS software, which reduces dramatically the overall system cost. Our system provides an easy access to change the functions of the system, with great possibility to satisfy the local needs. The design of our software will be presented with an explanation of the new supporting technologies that were to create the system. Finally, our software system has been validated using data from local road networks. Copyright © 2005 John Wiley & Sons, Ltd. [source]