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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 Eclipse 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.