As soon as I start a Spring Boot 2.2 application from Eclipse on my Windows 10 Laptop I notice around 10% of permanent CPU usage, and the clock freq. is also barely below 2 GHz, even if the application is sitting there idle.
When I stop the application, cpu usage drops to 1-2%, and the clock goes below 1 GHz.
The application does one sql query every minute, but apart of that does no processing while idle. It basically sits there waiting for requests.
How can I figure out what is causing this usage which seems to prevent the cpu (i7-5600U with 8GB ram) throttling down?
I use Java 1.8.0_221.
Edit 1 I tried running the compiled jar from cmd.exe, and then the idle cpu usage is low.
Edit 2 I tried disabling spring-boot-devtools in my pom.xml, and the idle cpu usage is low as well.
Edit 3 This is probably the issue: https://github.com/spring-projects/spring-boot/issues/9882 It feels like a FileWatcher is set up even for excluded folders and files, which in my case is bower_components with thousands of files.
