Version of JDK?
Also, what the OS shows reflects how much memory the JVM is consuming, not how much memory SQL Developer itself is using
Comparing java monitoring vs OS monitoring
and if i force a garbage collect...
SQL Developer is a big application, and we've added a TON of features since 4.1...putting it on an app server, you're going to need a TON of Memory, just like what you would need for something like Chrome
I'd try running it with java 11 or 12 with more aggressive garbage collection for starters.