Spring Boot is, by design, eager to load everything it sense you might need. Most of the memory usage is not Spring itself, it's the libraries it's pulling in on your behalf.

In Spring Boot 2 I'm told you can can use functional beans to cut down on RAM usage. Not sure how it works.

But really, it comes down to deciding if you need a dependency or not.

As is normal for questions about Spring Boot performance, Dave Syer has done a lot of investigating: https://github.com/dsyer/spring-boot-memory-blog