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diff --git a/doc/html/TechNotes/openmp-hdf5.html b/doc/html/TechNotes/openmp-hdf5.html deleted file mode 100644 index ff13b81..0000000 --- a/doc/html/TechNotes/openmp-hdf5.html +++ /dev/null @@ -1,67 +0,0 @@ -<pre> - Using HDF5 with OpenMP - ---------------------- - - -1. Introduction to OpenMP -------------------------- - - - For shared-memory parallelism - - A combination of library and directives - - Available for C/C++ and Fortran - - SGI leading effort - - Information at http://www.openmp.org and - http://www.sgi.com/software/openmp - -2. Programming(SGI MPISpro compiler and C language) ---------------------------------------------------- - - - Turn on compiler '-mp' option - - Include 'omp.h' library in program - - Use library functions, directives and environment variables - - -3. Sample Programs ------------------- - -Appendix A contains four OpenMP-HDF5 test programs. (They are derived from -the hdf5/examples/h5_write.c). The purpose of these program is to -test OpenMP parallelism with the HDF5 library. - -All tests were run on modi4 with SGI MPISpro compiler(cc) and make. -Program 1 and Program 2 are the working programs. Program 3 and Program 4 -work occasionally due to racing conditions. -Follow the following steps to try the programs. - - a. have your hdf5 library compiled, - b. go to hdf5/examples directory, - c. add -mp option to the end of the CFLAGS list in the Makefile. If you - have the compiled program in another directory, you should go to the - examples in that directory. - d. modify the hdf5/examples/h5_write.c according to the program attached - here. - e. use hdf5/tools/h5dump to examine the output file. - - -4. Conclusion -------------- - -It is not safe to invoke HDF5 library calls via multiple threads in an -OpenMP program. But if one serializes HDF5 calls as illustrated in Program 1, -the HDF5 library works correctly with the OpenMP programs. - -The serialization of HDF5 calls will slow down the OpenMP program unnecessarily. -Future study is needed to check possible ways to "un-seralize" the HDF5 calls. -One possibility is that the HDF5 library has a beta-version of Thread-safe -implmentation though it is for Pthreads environment. One can check on the -feasibility of running OpenMP programs with this version of HDF5 Thread-safe -library. - - - -<A HREF="openmp-hdf5.c">Appendix A: OpenMP-HDF5 Programs</A> - -------- -Updated: 2000/11/28 -Contact: hdfhelp@ncsa.uiuc.edu -</pre> |