I have java monolith application deployed on PCF with 4GB of memory allocation but some how I am facing instance crashing issue because of high memory utilisation. I took thread dump for analysis and found some issue with code.

Query: I have observed a strange behaviour where lets say service is using 3GB of space and if I trigger thread dump then memory get freed up and memory utilisation decrease down to 900 mb and service works smoothly.

So can anyone help me why this is happening. Is there any configuration in pcf which decreases memory or is there anything related to java garbage collection configuration.