[edderly]

If you're new to this area, I would first start by understanding which profiling tools you can use depending on the OS, languages and systems involved.

Even if your system is not C++, I've always enjoyed this talk and the subsequent discussion which tackles some of the problems associated with some programming practices and the impact on performance.

CppCon 2014: Mike Acton 'Data-Oriented Design and C++' https://youtu.be/rX0ItVEVjHc

[spacechild1]

I was just going to suggest that talk! Data locality is arguably the most important thing to consider when writing CPU intensive applications.