论文信息 - Techniques supporting threadprivate in OpenMP

Techniques supporting threadprivate in OpenMP

This paper presents the alternatives available to support threadprivate data in OpenMP and evaluates them. We show how current compilation systems rely on custom techniques for implementing thread-local data. But in fact the ELF binary specification currently supports data sections that become threadprivate by default. ELF naming for such areas is thread-local storage (TLS). Our experiments demonstrate that implementing threadprivate based on the TLS support is very easy, and more efficient. This proposal goes in the same line as the future implementation of OpenMP on the GNU compiler collection. In addition, our experience with the use of threadprivate in OpenMP applications shows that usually it is better to avoid it. This is because threadprivate variables reside in common blocks and they impede the compiler to fully optimize the code. So it is better to keep threadprivate as a temporary technique only to ease porting MPI codes to OpenMP

[1] Robert W. Numrich,et al. Co-arrays in the next Fortran Standard , 2005, FORF.

[2] Eduard Ayguadé,et al. A Library Implementation of the Nano-Threads Programming Model , 1996, Euro-Par, Vol. II.

[3] Milind Girkar,et al. Parafrase-2: an Environment for Parallelizing, Partitioning, Synchronizing, and Scheduling Programs on Multiprocessors , 1989, Int. J. High Speed Comput..

[4] Burkhard Monien,et al. International Parallel and Distributed Processing Symposium (IPDPS 2004) , 2006 .

[5] Xavier Martorell,et al. Nano-Threads Library Design, Implementation and Evaluation , 1995 .

[6] Shmuel Sagiv,et al. Optimizing C Multithreaded Memory Management Using Thread-Local Storage , 2005, CC.

[7] Sven Karlsson. An Introduction to Balder - An OpenMP Run-time Library for Clusters of SMPs , 2005, IWOMP.

[8] Eduard Ayguadé,et al. Nanos mercurium: A research compiler for OpenMP , 2004 .

[9] M. Gonzalez,et al. Exploiting pipelined executions in OpenMP , 2003, 2003 International Conference on Parallel Processing, 2003. Proceedings..

[10] Mitsuhisa Sato,et al. Design of OpenMP Compiler for an SMP Cluster , 1999 .

[11] Eduard Ayguadé,et al. Employing nested OpenMP for the parallelization of multi-zone computational fluid dynamics applications , 2004, 18th International Parallel and Distributed Processing Symposium, 2004. Proceedings..