[amadio]

For me, one of the biggest leaps in how I think about performance was when I learned about the Top-Down Micro-Architecture Analysis Method, by Ahmad Yasin from Intel. You can learn the main ideas from himself in the video below:

https://youtu.be/kjufVhyuV_A

The idea to classify cycles into front-end bound, backend bound, bad speculation or memory bound is brilliant. Once you know which one your program suffers from, it's easy to know what can be done to improve things.