Testing the performance of populating an array with structs.

benchmark.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define N 10000000

typedef struct _Foo {
    int name, id;
} Foo;

// Foo nodesGlobal[N];

void printUC(Foo uc) {
    printf("Foo { name = %d, id = %d }\n", uc.name, uc.id);
}

// allocate the memory chunk to fit n structs
Foo *allocFoos(long n) {
    return (Foo *) malloc(n * sizeof(Foo));
}

// populate the array with structs:
void createFoos(Foo *v, long n) {
    for (long i = 0; i < n; ++i) {
        v[i].name = i;
        v[i].id = i + 1;
    }
}

void benchmark(const char *name, Foo *v, long n) {
    printf("[[ %s ]]", name);

    clock_t begin = clock();
    time_t begin_wall = time(NULL);

    createFoos(v, n);

    clock_t end = clock();
    time_t end_wall = time(NULL);
    double elapsed = ((double) (end - begin)) / CLOCKS_PER_SEC * 1000;
    double elapsed_wall = ((double) (end - begin)) / 1000;
    printf("Time taken: %lf ms (cpu) %lf ms (wall)\n", elapsed, elapsed_wall);
}

int main() {
    printf("%s", "Starting the benchmark\n");

    Foo *nodes = allocFoos(N);
    benchmark("Malloced-array", nodes, N);
    free(nodes);

    printf("%s", "Done\n");
}