The default value for the maximum heap size (
-Xmx) is 25% of the available memory with a maximum of 25 GB. However, where there is 2 GB or less of physical memory, the value set is 50% of available memory with a minimum value of 16 MB and a maximum value of 512 MB. In OpenJ9 0.18.0 and earlier releases the default is half the available memory with a minimum of 16 MB and a maximum of 512 MB. Enable this option to revert to the earlier default value.
Restriction: This option is supported only on Java™ 8. It is ignored on Java 11 and later versions.