Two alternative dual-level parallel implementations of the Multiblock Grid Princeton Ocean Model (MGPOM) are compared in this paper. The first one combines the use of two programming paradigms: message passing with the Message Passing Interface (MPI) and shared memory with OpenMP (version called MPI-OpenMP); the second uses only OpenMP (version called OpenMP-Only). MGPOM is a multiblock grid co...

In this paper we present a technique based on code templates, oriented to source to source code transformations for OpenMP parallelization. Our goal is to provide an OpenMP compilation infrastructure that includes a reconfigurable code generation phase, targetting different OpenMP runtime systems or explore different translation strategies for OpenMP constructs. We describe the main OpenMP tran...

Asynchronous tasks make it easy to express the parallelism in a broad variety of computations and are especially useful for writing parallel applications with irregular and/or dynamic workloads. Their introduction into the OpenMP specification has greatly extended the scope of this API. Yet the body of benchmarks using OpenMP tasks remains minimal. The EPCC OpenMP Microbenchmarks provide measur...

OpenMP is a de facto API for parallel programming in C/C++ and Fortran on shared memory and distributed shared memory platforms. It is also being increasingly used with MPI to form a hybrid programming model and is expected to be a promising candidate to exploit emerging multicore architectures. An OpenMP cost model is an analytical model that reflects the characteristics of OpenMP applications...

OpenMP is the de facto standard to exploit the on-node parallelism in new generation supercomputers. Despite its overall ease of use, even expert users are known to create OpenMP programs that harbor concurrency errors, of which one of the most insidious of errors are data races. OpenMP is also a rapidly evolving standard, which means that future data races may be introduced within unfamiliar c...

The OpenMP 3.0 standard should be released for public comment by the time of this conference. OpenMP 3.0 is the first major upgrade of the OpenMP standard since the merger of the C and Fortran standards in OpenMP 2.5. This talk will give an overview of the new features in the OpenMP standard and show how they help to extend the range of problems for which OpenMP is suitable. Even with multi-cor...

In this paper, we present an implementation of OpenMP compiler for a page-based software distributed shared memory system, SCASH on a cluster of PCs. For programming distributed memory multiprocessors such as clusters of PC/WS and MPP, message passing is usually used. A message passing system requires programmers to explicitly code the communication and makes writing parallel programs cumbersom...

OpenMP has been for many years the most widely used programming model for shared memory architectures. Periodically, new features are proposed and some of them are finally selected for inclusion in the OpenMP standard. The OmpSs programming model developed at the Barcelona Supercomputing Center (BSC) aims to be an OpenMP forerunner that handles the main OpenMP constructs plus some extra feature...

The recent parallel language standard for shared memory multiprocessor (SMP) machines, OpenMP, promises a simple and portable interface for programmers who wish to exploit parallelism explicitly. In this paper, we present our effort to develop portable compilers for the OpenMP parallel directive language. Our compiler consists of two parts. Part one is an OpenMP parallelizer, which transforms s...

We developed an OpenMP compiler, called Omni. This paper describes a performance evaluation of the Omni OpenMP compiler. We take two commercial OpenMP C compilers, the KAI GuideC and the PGI C compiler, for comparison. Microbenchmarks and a program in Parkbench are used for the evaluation. The results using a SUN Enterprise 450 with four processors show the performance of Omni is comparable to ...