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-XX:[+|-]UseMediumPageSize

AIX only

This option is used to enable or disable the default definition setting of the LDR_CNTRL environment variable.

Syntax

    -XX:[+|-]UseMediumPageSize
Setting Effect Default
-XX:+UseMediumPageSize Enable yes
-XX:-UseMediumPageSize Disable

Explanation

On AIX systems, by default the Java launcher sets the LDR_CNTRL environment variable as TEXTPSIZE=64K@DATAPSIZE=64K@STACKPSIZE=64K@SHMPSIZE=64K to specify medium page sizes (64 KB) for the text, data, stack, and shared memory segments. This default setting is used to improve performance.

You can use -XX:-UseMediumPageSize to disable the default setting of the LDR_CNTRL environment variable. When this option is used, the Java launcher uses the default AIX page sizes (4 KB for each segment).

You can re-enable the default setting with the -XX:+UseMediumPageSize option.

See also