Spring boot application is not reducing the memory when there is no request on openshift container

Question

My spring boot application is comprised of 8 APIs & deployed applications in an open shift container. I have tested one of the APIs using the JMeter for the load testing till the memory utilized up to 400 to 420Mi but the problem is when I have stopped the load testing still, it's showing the 420Mi on the open shift container. Help me to understand why the Pod or Java is not reducing the memory when it's not used. Configured the request as 150mi & limit as 512mi Java version: 1.8