First of all, I have never done performance analysis. I am a newcomer. When I was maintaining the previous code, the project had a very high CPU usage, which could probably eat up the CPU. Now that the original code maintainer has resigned, it is difficult to ask anyone. , I have no choice but to come here to ask all the veterans, what should I do when encountering this situation, or how should I start the analysis, please, newbies, please help