The following table shows the values that are used when -XX:+UseContainerSupport is set: Less than 1 GB 50% <size> 1 GB - 2 GB <size> - 512 MB Greater than 2 GB 75% <size> The default heap size is capped at 25 GB The default heap size for containers takes affect only when the following conditions are met: The application is running in a container environment. The memory limit for the container is set. The -XX:+UseContainerSupport option is set, which is the default behavior.