spring boot - Why is the Heap Memory Usage of a SpringBoot application keeps increasing?

Question

I created and ran a simple SpringBoot application to accept some requests. I used jconsole to check the Heap Memory Usage and I saw this periodic increase followed by GC, I don't know the reason for the increases. Are there any Objects keep being created (because I think the instances are imported to container when the application starts)?

question from:https://stackoverflow.com/questions/65650438/why-is-the-heap-memory-usage-of-a-springboot-application-keeps-increasing

Answer 1

Spring boot has background processes which may consume your resources despite on absent requests to your app, for example jobs, etc.

Those spikes are expected and regular for any Java app based on any more less complex framework. GC algorithm depends on your jvm version, but could be overridden. The graph shows normal situation, from time to time memory consumed for some activities and after some time GC wake up and do the cleaning.

In case if you want to check what exactly objects caused memory spike you may try to use Java Flight Recorder or regular heap dump analysis using Eclipse memory analyser. For current case Java Flight Recorder would be more convenient and suitable.