Java Threads vs OS Threads

Question

Looks like I have messed up with Java Threads/OS Threads and Interpreted language.

Before I begin, I do understand that Green Threads are Java Threads where the thre

Answer 1

Threading and running a byte code are separate issues. Green threads are used by JVM on platforms that do not have native support of threads. (IMHO I do not know which platform does not support threads).

Byte code is interpreted in real time and executed on native platform by JVM. JVM decides what are the most popular code fragments and performs so called Just in time compiling of these fragments, so it does not have to compile them again and again. This is independent on threading. If for example you have one thread that executes the same code fragment in loop you this fragment will be cached by just in time compiler.

Bottom line: do not worry about performance and threads. Java is strong enough to run everything you are coding.