localityofreference

From what I understand, spacial locality has to do with nearby memory being used in the nearby future. However I was wondering if a loop is executed many times, does this lead to good spacial locality? Thanks in advance, and sorry if I'm hard to understand. The number of iterations of a loop doesn't necessarily affect spatial locality. What the loop is doing does. In practice, the key to spatial locality really has to do with cache lines. In simple terms, a program that limits its accesses to a small number of different cache lines will exhibit more cache hits, and thus better performance. A

Say we have an unsorted array and linked list. The worst case when searching for an element for both data structures would be O( n ), but my question is: Would the array still be way faster because of the use of spatial locality within the cache, or will the cache make use of branch locality allowing linked lists to be just as fast as any array ? My understanding for an array is that if an element is accessed, that block of memory and many of the surrounding blocks are then brought into the cache allowing for much faster memory accesses. My understanding for a linked list is that since the

for(int i = 0; i<100; i++) for(int j = 0; j<100; j++) array[j][i] = 0; // array[i][j] = 0; My professor said it was much more costly to initialize a two dimensional array in the first way as opposed to the second. Can someone explain what is going on underneath the hood which makes that the case? Or, do the two means of initialization have equal performance? templatetypedef As @dlev mentioned, this is due to locality of reference and has to do with how the physical hardware in the computer works. Inside the computer, there are many different types of memory. Typically, only certain memory