What is Busy Spinning? Why should you use it in Java?

After TensorFlow, should I really bother with learning C++ for machine learning or should I stick to Python?

What precautions should one take to speed up a NodeJS application?

I want to know of different ways NodeJS developers use, to identify bottlenecks in a NodeJS applications; so that I'm not thrown back into a corner once I am in a sufficiently advanced stage in my application, and my codebase would need a heavy refac...