Comment by pjmlp

You can analyze Assembly code just like in any other AOT compiled language.

Have a go at in Godbolt, https://godbolt.org/

OCaml also integrates with perf on Linux,

https://ocaml.org/learn/tutorials/performance_and_profiling....

Some performance tips from an old partially archived page.

https://hackerfall.com/story/writing-performance-sensitive-o...

And if you are feeling fancy, doing some pointer style programming

https://ocaml.org/learn/tutorials/pointers.html