[[PageOutline]] ◢ <[wiki:VNU120925/Lab1 實作一]> | <[wiki:VNU120925 回課程大綱]> ▲ | <[wiki:VNU120925/Lab3 實作三]> ◣ = 實作二 = {{{ #!html
多核心程式設計 : OpenMP
Multi-Cores Programming : OpenMP
}}} == 編譯環境檢驗 Compiler Version Check == * GCC 4.2 以上版本就有支援 OpenMP 了....用 "gcc '''-fopenmp'''" 就可以編譯 * 確認目前 gcc 版本，須大於 4.2 以後的版本 {{{ ~$ gcc -v Using built-in specs. Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Debian 4.4.5-8' --with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.4 --enable-shared --enable-multiarch --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.4 --libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc --with-arch-32=i586 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.4.5 (Debian 4.4.5-8) }}} == Example 1 : !HelloWorld == * 首先從 [https://computing.llnl.gov/tutorials/openMP/exercise.html OpenMP Exercise] 下載 omp_hello.c {{{ ~$ wget https://computing.llnl.gov/tutorials/openMP/samples/C/omp_hello.c }}} * 使用 GCC 編譯 omp_hello.c {{{ ~$ gcc -o omp_hello -fopenmp omp_hello.c }}} * 執行 omp_hello 執行檔 {{{ ~$ ./omp_hello Hello World from thread = 2 Hello World from thread = 3 Hello World from thread = 0 Number of threads = 4 Hello World from thread = 1 }}} == Example 2 : Loop work-sharing == * 首先從 [https://computing.llnl.gov/tutorials/openMP/exercise.html OpenMP Exercise] 下載 omp_workshare1.c {{{ ~$ wget https://computing.llnl.gov/tutorials/openMP/samples/C/omp_workshare1.c }}} * 使用 GCC 編譯 omp_workshare1.c {{{ ~$ gcc -o omp_workshare1 -fopenmp omp_workshare1.c }}} * 執行 omp_workshare1 執行檔 {{{ ~$ ./omp_workshare1 ~$ ./omp_workshare1 Thread 3 starting... Thread 1 starting... Number of threads = 4 Thread 0 starting... Thread 0: c[20]= 40.000000 Thread 0: c[21]= 42.000000 Thread 0: c[22]= 44.000000 Thread 0: c[23]= 46.000000 Thread 0: c[24]= 48.000000 Thread 0: c[25]= 50.000000 ... skipped ... Thread 2 starting... Thread 2: c[90]= 180.000000 Thread 2: c[91]= 182.000000 Thread 2: c[92]= 184.000000 Thread 2: c[93]= 186.000000 Thread 2: c[94]= 188.000000 ... skipped ... Thread 3: c[0]= 0.000000 Thread 3: c[1]= 2.000000 Thread 3: c[2]= 4.000000 Thread 3: c[3]= 6.000000 Thread 3: c[4]= 8.000000 Thread 3: c[5]= 10.000000 ... skipped ... Thread 1: c[10]= 20.000000 Thread 1: c[11]= 22.000000 Thread 1: c[12]= 24.000000 Thread 1: c[13]= 26.000000 Thread 1: c[14]= 28.000000 }}} == OpenMP 參考資料 == * 多核心平行化程式設計 Multi-Cores Programming * <官網> [https://computing.llnl.gov/tutorials/openMP/ OpenMP Tutorial] * <官網> [https://computing.llnl.gov/tutorials/openMP/exercise.html OpenMP Exercise] * [http://www.nersc.gov/nusers/help/tutorials/openmp/ OpenMP Tutorial] at National Energy Research Scientific Computing Center (NERSC) * [http://kheresy.wordpress.com/2006/06/09/%E7%B0%A1%E6%98%93%E7%9A%84%E7%A8%8B%E5%BC%8F%E5%B9%B3%E8%A1%8C%E5%8C%96%E6%96%B9%E6%B3%95%EF%BC%8Dopenmp%EF%BC%88%E4%B8%80%EF%BC%89%E7%B0%A1%E4%BB%8B/ 簡易的程式平行化方法－OpenMP（一）簡介] * [http://kheresy.wordpress.com/2006/09/13/%E7%B0%A1%E6%98%93%E7%9A%84%E7%A8%8B%E5%BC%8F%E5%B9%B3%E8%A1%8C%E5%8C%96%EF%BC%8Dopenmp%EF%BC%88%E4%BA%8C%EF%BC%89%E8%AA%9E%E6%B3%95%E8%AA%AA%E6%98%8E/ 簡易的程式平行化－OpenMP（二）語法說明] * [http://kheresy.wordpress.com/2006/09/15/%E7%B0%A1%E6%98%93%E7%9A%84%E7%A8%8B%E5%BC%8F%E5%B9%B3%E8%A1%8C%E5%8C%96%EF%BC%8Dopenmp%EF%BC%88%E4%B8%89%EF%BC%89%E7%AF%84%E4%BE%8B-parallel%E3%80%81section/ 簡易的程式平行化－OpenMP（三）範例 parallel、section] * [http://kheresy.wordpress.com/2006/09/15/%E7%B0%A1%E6%98%93%E7%9A%84%E7%A8%8B%E5%BC%8F%E5%B9%B3%E8%A1%8C%E5%8C%96%EF%BC%8Dopenmp%EF%BC%88%E5%9B%9B%EF%BC%89%E7%AF%84%E4%BE%8B-for/ 簡易的程式平行化－OpenMP（四）範例 for] * [http://kheresy.wordpress.com/2006/09/22/%E7%B0%A1%E6%98%93%E7%9A%84%E7%A8%8B%E5%BC%8F%E5%B9%B3%E8%A1%8C%E5%8C%96%EF%BC%8Dopenmp%EF%BC%88%E4%BA%94%EF%BC%89-%E8%AE%8A%E6%95%B8%E7%9A%84%E5%B9%B3%E8%A1%8C%E5%8C%96/ 簡易的程式平行化－OpenMP（五） 變數的平行化] == Perl v.s. multicore == * [http://search.cpan.org/~dlux/Parallel-ForkManager-0.7.9/ Parallel::ForkManager] - A simple parallel processing fork manager * [http://stackoverflow.com/questions/1961682/how-can-i-make-my-perl-script-use-multiple-cores-for-child-processes How can I make my Perl script use multiple cores for child processes?] * [http://computationalbiologynews.blogspot.com/2008/07/harnessing-power-of-multicore.html Harnessing the power of multicore] == Python v.s. multicore == * [http://stackoverflow.com/questions/203912/does-python-support-multiprocessor-multicore-programming Does python support multiprocessor/multicore programming?] * Parallel Python - [http://www.parallelpython.com/content/view/17/31/ Examples] * [http://code.google.com/p/python-multiprocessing/ python-multiprocessing] - Python 2.5/2.4 back port of the multiprocessing package