Operating System

What is locality? How can you address locality after studying the concept of memory? Explain it for both spatial locality as well as temporal locality. How can the locality of the following program be improved:

int sumarray3d(int a[M][N][N]) {

int i, j, k, sum = 0;

for (i = 0; i < N; i++)

for (j = 0; j < N; j++)

for (k = 0; k < M; k++) sum += a[k][i][j]; return sum;

}