Structure of arrays and array of structures - performance difference

Question

I have a class like this:

//Array of Structures
class Unit
{
  public:
    float v;
    float u;
    //And similarly many other variables of float type, upto         


        

Answer 1

Structure of arrays is not cache friendly in this case.

You use both u and v together, but in case of 2 different arrays for them they will not be loaded simultaneously into one cache line and cache misses will cost huge performance penalty.

_mm_prefetch can be used to make AoS representation even faster.