OpenMP News

»OpenMP 3.1 Support in Clang Announced

The Clang community has announced the availability of a full OpenMP 3.1 support implementation in the Clang compiler:

“This project implements OpenMP support in the Clang C language family front-end for the LLVM compiler. The current scope of the project is to support the OpenMP 3.1 specification.”

The project is hosted here:

It is based on clang 3.3 (and will be updated as new clang/llvm releases become available); also, we plan to eventually contribute everything to the clang trunk (initial patches have already been committed). This implementation supports 3.1 version of OpenMP standard in full; it passes all OpenMP tests we tried with it so far (this includes OpenMP Validation Suite from OpenUH Research Compiler, SPEC OMP2012 and internal Intel test suites). Performance-wise, it demonstrates similar gains and scalability as other compilers with OpenMP support.

»OpenMP Consortium Announces Red Hat As New Member

26 vendors and research organizations collaborating on standard parallel programming model

Red Hat has joined the OpenMP Architecture Review Board (ARB), a group of leading hardware and software vendors and research organizations creating the standard for today’s most prevalent shared-memory parallel programming model.

“As a leading proponent of OpenMP, Red Hat is thrilled to officially join the OpenMP ARB,” said Mike Werner, senior director, ISV and developer ecosystems, Red Hat. “We believe that the OpenMP model is important in simplifying parallel processing efforts, and implement the standard in Red Hat Enterprise Linux, including Red Hat Enterprise Linux 6.”

Red Hat is the world’s leading provider of open source solutions, using a community-powered approach to reliable and high-performing cloud, Linux, middleware, storage and virtualization technologies. The company’s membership in the OpenMP ARB exemplifies a long-standing commitment to the development and support of tools and standards that help advance open source technology and its adoption within the developer community.

“I am very pleased to have Red Hat participate in the OpenMP family”, said Michael Wong, OpenMP CEO. “Red Hat has a long tradition of supporting OpenMP with rapid GCC implementations and strong commitment to open standards. This will help to ensure deeper collaboration.”

The OpenMP ARB now has 14 permanent members and 12 auxiliary members. Permanent members, including Red Hat, are vendors who have a long-term interest in creating products for OpenMP, while auxiliary members are organizations with an interest in the standard but that do not create or sell OpenMP products.

»OpenMP 4.0 Specifications Released

The OpenMP 4.0 API Specification is released with Significant New Standard Features

The OpenMP 4.0 API supports the programming of accelerators, SIMD programming, and better optimization using thread affinity

The OpenMP Consortium has released OpenMP API 4.0, a major upgrade of the OpenMP API standard language specifications. Besides several major enhancements, this release provides a new mechanism to describe regions of code where data and/or computation should be moved to another computing device.

Bronis R. de Supinski, Chair of the OpenMP Language Committee, stated that “OpenMP 4.0 API is a major advance that adds two new forms of parallelism in the form of device constructs and SIMD constructs. It also includes several significant extensions for the loop-based and task-based forms of parallelism already supported in the OpenMP 3.1 API.

The 4.0 specification is now available on the »OpenMP Specifications page.

Standard for parallel programming extends its reach

With this release, the OpenMP API specifications, the de-facto standard for parallel programming on shared memory systems, continues to extend its reach beyond pure HPC to include DSPs, real time systems, and accelerators. The OpenMP API aims to provide high-level parallel language support for a wide range of applications, from automotive and aeronautics to biotech, automation, robotics and financial analysis.

New features in the OpenMP 4.0 API include:

· Support for accelerators. The OpenMP 4.0 API specification effort included significant participation by all the major vendors in order to support a wide variety of compute devices. OpenMP API provides mechanisms to describe regions of code where data and/or computation should be moved to another computing device. Several prototypes for the accelerator proposal have already been implemented.

· SIMD constructs to vectorize both serial as well as parallelized loops. With the advent of SIMD units in all major processor chips, portable support for accessing them is essential. OpenMP 4.0 API provides mechanisms to describe when multiple iterations of the loop can be executed concurrently using SIMD instructions and to describe how to create versions of functions that can be invoked across SIMD lanes.

· Error handling. OpenMP 4.0 API defines error handling capabilities to improve the resiliency and stability of OpenMP applications in the presence of system-level, runtime-level, and user-defined errors. Features to abort parallel OpenMP execution cleanly have been defined, based on conditional cancellation and user-defined cancellation points.

· Thread affinity. OpenMP 4.0 API provides mechanisms to define where to execute OpenMP threads. Platform-specific data and algorithm-specific properties are separated, offering a deterministic behavior and simplicity in use. The advantages for the user are better locality, less false sharing and more memory bandwidth.

· Tasking extensions. OpenMP 4.0 API provides several extensions to its task-based parallelism support. Tasks can be grouped to support deep task synchronization and task groups can be aborted to reflect completion of cooperative tasking activities such as search. Task-to-task synchronization is now supported through the specification of task dependency.

· Support for Fortran 2003. The Fortran 2003 standard adds many modern computer language features. Having these features in the specification allows users to parallelize Fortran 2003 compliant programs. This includes interoperability of Fortran and C, which is one of the most popular features in Fortran 2003.

· User-defined reductions. Previously, OpenMP API only supported reductions with base language operators and intrinsic procedures. With OpenMP 4.0 API, user-defined reductions are now also supported.

· Sequentially consistent atomics. A clause has been added to allow a programmer to enforce sequential consistency when a specific storage location is accessed atomically.

This represents collaborative work by many of the brightest in industry, research, and academia, building on the consensus of 26 members. We strive to deliver high-level parallelism that is portable across 3 widely-implemented common General Purpose languages, productive for HPC and consumers, and delivers highly competitive performance. I want to congratulate all the members for coming together to create such a momentous advancement in parallel programming, under such tight constraints and industry challenges.
With this release, the OpenMP API will move immediately forward to the next release to bring even more usable parallelism to everyone.
– Michael Wong, CEO OpenMP ARB.

»Recently Published

  • OpenMP Programming on Intel R Xeon Phi TM Coprocessors: An Early Performance Comparison
    Tim Cramer, Dirk Schmidl, Michael Klemmy, Dieter an Mey

»Recently Published…

Recent publications of interest regarding OpenMP on the web:

»Barcelona Supercomputing Center Joins the OpenMP Consortium

24 vendors and research organizations now collaborating on developing shared-memory parallel programming model

Champaign, Illinois — May 2, 2013 — The Barcelona Supercomputing Center (BSC) has joined the OpenMP ARB, a group of leading hardware and software vendors and research organizations creating the standard for the most popular shared-memory parallel programming model in use today.

“We are proud to share our 15 years’ experience developing support for parallel programming models within the OpenMP community.”, says Mateo Valero, director of BSC, “Our researchers have been involved in OpenMP since the beginning, through cOMPunity. BSC has participated in the definition of the tasking model, lately with the inclusion of task dependences.”

“I look forward to BSC continuing their excellent technical contribution from the past into the future.”, says Michael Wong, OpenMP CEO.

Barcelona Supercomputing Center is an HPC research center that holds a significant group of Computer Science researchers and closely collaborates with IT Industry. Its Computer Science research covers all levels from the computer architecture to the parallel applications.

The OpenMP Architecture Review Board (ARB) now has 13 permanent members and 11 auxiliary members. Permanent members are vendors creating products for OpenMP. These are AMD, CAPS-Enterprise, Convey Computer, Cray, Fujitsu, HP, IBM, Intel, NEC, NVIDIA, Oracle Corporation, The Portland Group, Inc., and Texas Instruments. Auxiliary members are organizations with an interest in the standard but that do not sell OpenMP products. They are ANL, ASC/LLNL, BSC, cOMPunity, EPCC, LANL, NASA, ORNL, RWTH Aachen University, Sandia National Lab and the Texas Advanced Computing Center.

»Michael Wong on OpenMP 4.0

Michael Wong, CEO of the OpenMP Architecture Review Board (ARB), comments in his blog about the forthcoming OpenMP 4.0 specifications:

So much has been happening in OpenMP since SC 12 that we I hope to capture it all in this post while flying back from a C++ Standard meeting.

When we last spoke, you heard that OpenMP has introduced a Technical Report process to improve its agility at issuing interim specifications, and more importantly to obtain user feedback. We used that process to introduce TR1 for accelerator support. We also released Release Candidate 1 which had 31 feature/defect fixes.

Since then, we had the Houston F2F meeting in January 2013, where we gathered to complete the work of

  • Incorporating feedback for accelerators and strengthen NVIDIA support where synchronization between teams are not implicit
  • Complete work on cancellation
  • Improve taskgroup support
  • Improve Fortran 2008 support
  • Fully specify affinity
  • Improved SIMD
  • Generalized Tooling and Debugger support


You can read it all »here.

»IWOMP 2013 - Canberra AUSTRALIA - September

IWOMP 2013 Canberra

9th International Workshop on OpenMP — September 16-18, 2013

The »International Workshop on OpenMP (IWOMP) is an annual workshop dedicated to the promotion and advancement of all aspects of parallel programming with OpenMP. It is the premier forum to present and discuss issues, trends, recent research ideas and results related to parallel programming with OpenMP. The international workshop affords an opportunity for OpenMP users as well as developers to come together for discussions and sharing new ideas and information on this topic.

The deadline for paper submissions has been extended to May 10th.

IWOMP 2013 will be a three-day event. The first day will consist of tutorials focusing on topics of interest to current and prospective OpenMP developers, suitable for both beginners as well as those interested in learning of recent developments in the evolving OpenMP standard. The second and third days will consist of technical papers and panel sessions during which research ideas and results will be presented and discussed.

Go to » for more information.

The OpenMP API supports multi-platform shared-memory parallel programming in C/C++ and Fortran. The OpenMP API defines a portable, scalable model with a simple and flexible interface for developing parallel applications on platforms from the desktop to the supercomputer.
»Read about