We are finishing this chapter by talking about iterating over elements and looking at some ways to improve the performance when iterating over array-like data structures. We already mentioned two important factors for performance when accessing data: spatial locality and temporal locality. When iterating over elements stored in contiguous memory, we will see that by keeping our objects small, we will increase the probability that the data we need is already cached thanks to spatial locality. Obviously, this will have a great impact on the performance.
Recall the cache thrashing example shown in the beginning of this chapter where we iterated over a matrix. It demonstrated that we sometimes need to think about in what way we ...
