Optimizing linear access to arrays with pre-fetching and cache in C

Question

disclosure: I\'ve tried similar question on programmers.stack, but that place is nowhere near activity stack is.

Intro

I tend to work with lots

Answer 1

You should compile with a recent GCC (so having compiled your GCC 5.2 is a good idea, in November 2015), and you should enable optimizations for your particular platform, so I suggest compiling with gcc -Wall -O2 -march=native at least (try also to replace -O2 with -O3).

^{(Don't benchmark your programs without enabling optimizations in your compiler)}

If you are concerned with cache effects, you might play with __builtin_prefetch, but see this.

Read also about OpenMP, OpenCL, OpenACC.