| 1 | #ifdef USE_OMP |
| 2 | int openmptest(){ |
| 3 | int start = timeOfDayinMS(); |
| 4 | long int sum=0; |
| 5 | int i,j; |
| 6 | |
| 7 | #pragma omp parallel for shared(sum) |
| 8 | for (i=0; i<10;i++){ |
| 9 | printf("num theads: %i\n",omp_get_thread_num()); |
| 10 | long int k=0; |
| 11 | for (j=0; j<40000;j++){ |
| 12 | k+=sqrt(j); |
| 13 | } |
| 14 | #pragma omp atomic |
| 15 | sum+=k; |
| 16 | } |
| 17 | int end = timeOfDayinMS(); |
| 18 | fprintf(stderr, "Sum: %li\n",sum); |
| 19 | return end-start; |
| 20 | } |
| 21 | int openmp(){ |
| 22 | fprintf(stderr, "Processors: %i, Max # theads: %i\n", omp_get_num_procs(), omp_get_max_threads()); |
| 23 | |
| 24 | int time, timeref; |
| 25 | omp_set_dynamic( 0 ); |
| 26 | omp_set_num_threads( 1 ); |
| 27 | fprintf(stderr,"********** omp speedtest:\n"); |
| 28 | time = openmptest(); |
| 29 | fprintf(stderr,"***C time: %i ms\n", time); |
| 30 | timeref=time; |
| 31 | omp_set_dynamic( 0 ); |
| 32 | omp_set_num_threads( 2 ); |
| 33 | time = openmptest(); |
| 34 | fprintf(stderr,"***C (2)time: %i ms, Speedup %f\n", time, |
| 35 | (double)timeref/time); |
| 36 | omp_set_dynamic( 1 ); |
| 37 | return 1; |
| 38 | } |
| 39 | #endif |