hpc-2022-g3/openmp/lab1/.solutions/exercise2.c

/*
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 * Copyright (c) 2020, Alessandro Capotondi
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/**
 * @file exercise2.c
 * @author Alessandro Capotondi
 * @date 27 Mar 2020
 * @brief Exercise 2
 * 
 * @see https://dolly.fim.unimore.it/2019/course/view.php?id=152
 */

#include <stdio.h>
#include <omp.h>

#include "utils.h"

/**
 * @brief EX 2 - Data parallelism: parallel loop ** 1 to 16 THREADS **
 *
 * a) Parallelize loop w/static scheduling
 * b) Parallelize loop w/dynamic scheduling for chunks = NITER/NTHR (same as static) and 1 (finest granularity)
 * c) Same as 2a + 2b, with 1<<20 loop iterations and work(10)
 * 
 * @return void
 */
void exercise()
{

#if 0 //2a
#pragma omp parallel for schedule(static) num_threads(NTHREADS)
    for(int i=0; i< 1<<10; i++)
    {
        DEBUG_PRINT("%hu: I am executing iteration %hu!\n", omp_get_thread_num(), i);
        work(1<<10);
        DEBUG_PRINT("%hu: Done with iteration %hu!\n", omp_get_thread_num(), i);
    }
#endif

#if 0 //2b
    int M = (1<<10) / NTHREADS;
    //#pragma omp parallel for schedule(dynamic,M) num_threads(NTHREADS)
#pragma omp parallel for schedule(dynamic, 1) num_threads(NTHREADS)
    for(int i=0; i< 1<<10; i++)
    {
        DEBUG_PRINT("%hu: I am executing iteration %hu!\n", omp_get_thread_num(), i);
        work(1<<10);
        DEBUG_PRINT("%hu: Done with iteration %hu!\n", omp_get_thread_num(), i);
    }
#endif

#if 1 //2c
    int M = (1 << 20) / NTHREADS;
//#pragma omp parallel for schedule(static) num_threads(NTHREADS)
//#pragma omp parallel for schedule(dynamic,M) num_threads(NTHREADS)
#pragma omp parallel for schedule(dynamic, 1) num_threads(NTHREADS)
    for (int i = 0; i < 1 << 20; i++)
    {
        DEBUG_PRINT("%hu: I am executing iteration %hu!\n", omp_get_thread_num(), i);
        work(10);
        DEBUG_PRINT("%hu: Done with iteration %hu!\n", omp_get_thread_num(), i);
    }
#endif
}