I used 4 or 5 performance tools to look at the performance of Oil shell, and uftrace was one of the most important ones.
I hope to write a blog post about it soon. The overall results were very good -- Oil is now faster than bash despite doing more parsing by design -- though the biggest win was translating the code to C++ from Python :)
So it's unusual, but after translation, uftrace was a winner, and I used it largely by counting function calls and allocations, not measuring timing. Although you can use it in many different ways.
Oil's Parser is 160x to 200x Faster Than It Was 2 Years Ago
http://www.oilshell.org/blog/2020/01/parser-benchmarks.html
Another lesson is that aside from the big difference in execution speed, tools for measuring C++ performance are just way better than those for Python. Debugging tools are also better. Of course I still avoid C++ for most problems because of build times, headers, memory management, library style smorgasbord, etc.