Do Java programmers need to know the OS?

Question

Java

Found an interesting course on operating systems. To what extent does a Java programmer need all this? Or is it more relevant for a C++ programmer? Algorithms seem to be useful for everyone to know, but operating systems? Serious question for me, please no jokes.

Answer 1

Yes need! At the very least, you need a general idea. Since any program is executed in the environment of the operating system.
Take the server side. You don't just run tomcat/jboss/jetty/whatever. You most likely have a database, a proxy server. There is monitoring, orchestration, networks... it all depends on the operating system, settings, access rights. If you do not understand anything at all, then simple errors, such as a busy port or a limit on open descriptors, can be searched for days.
As a result, the tests pass, and everything works, but the load does not hold! Or it crashes with an incomprehensible result.
I'm not talking about desktop applications, utilities, cli and gui.
If you want to make really portable applications, you have to dig a little deeper than Java.
Well, an example. Now I am writing, yes, yes, an audio player with binding to gstreamer. I develop on a mac, debug on linux, and the target system is on arm with armbian. Something like this.