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(64-bit only)

This Oracle HotSpot option enables or disables compressed references in 64-bit JVMs. The option is recognized by the OpenJ9 VM and is provided to help when porting applications from the HotSpot JVM to the OpenJ9 VM. This option might not be supported in subsequent releases.


Setting Effect Default
-XX:+UseCompressedOops Enable
-XX:-UseCompressedOops Disable

The -XX:+UseCompressedOops option is similar to specifying -Xcompressedrefs. Compressed references are used by default when the maximum memory size for an application is set above a platform-specific value. For more information, see -Xcompressedrefs.