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Sets the heap expansion allocation increment.

You can use the -verbose:sizes option to find out the values that the VM is currently using.


Setting Effect Default
-Xmoi<size> Sets the heap expansion allocation increment See Notes


  • By default, the increment size (-Xmoi) is calculated on the expansion size, set by -Xmine and -Xminf. If you set -Xmoi to zero, no expansion is allowed.
  • For the gencon GC policy, the expansion increment applies to the tenure area of the heap.

This option is not supported for the metronome GC policy, because the heap is always fully expanded.

See Using -X command-line options for more information about the <size> parameter.

See also