C没有可用的程序内存：不安全地调用malloc错误

Question

I am trying to create all of the matrices from size 10x10 to 1000x1000 around 980 I start running out of memory even though the program is clearly not using all 4GB of my system. My code looks like:

    double **a3;
    double **result;
    a3 = malloc(k * sizeof(double *));
    for(i = 0; i < k; i++)
    {
        a3[i] = malloc(sizeof(double));
    }
    result = malloc(k * sizeof(double *));
    for(i = 0; i < k; i++)
    {
        result[i] = malloc(k * sizeof(double));
    }
    for(i = 0; i < k; i++)
    {
        for( j = 0; j < k; j++)
        {
            a3[i][j] = 0;
            result[i][j] = 0;
        }
    }
    ...
    for(i = 0; i < k; i++)
{
    free(a3[i]);
    free(result[i]);
}
free(a3);
free(result);

I am not sure why this doesn't work (it does work if I use int arrays but I need double arrays)

I am using Mac OSX 64bit

Answer 1

I'm not sure how 'clear' you actually are about not using all the memory that's available to your program . If I'm figuring rightly, you end up allocating a total of 333,833,185 doubles. At eight bytes each, that's over 2.5GB.

Not sure how much is available to your C compiler's memory management facilities... why not write a simple program that discovers what the biggest amount of memory you could malloc() is?