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-Xcompressedrefs / -Xnocompressedrefs

(64-bit only)

These options enable or disable the use of compressed references.

Restriction: You cannot include -Xcompressedrefs in the options file (see -Xoptionsfile).


Setting Action Default
-Xcompressedrefs Enable compression yes (see Default behavior)
-Xnocompressedrefs Disable compression

Default behavior

Compressed references are enabled by default when -Xmx ≤ 57 GB.

z/OS®: This threshold value assumes that you have APAR OA49416 installed. If you do not have the APAR installed, the threshold value is 25 GB.

AIX® and Linux®: For the metronome garbage collection policy, the threshold is 25 GB.

See also