MAXPRIM
Specify the MAXPRIM option for the named output descriptor to set the upper limit on the value that the PCTPRIM option calculates.

Specifying a nonzero value for integer establishes an upper limit for primary space allocation. A value of 0 indicates no limit.
UNLOAD PLUS ignores this option for referenced files.
When you are using the SMS-guaranteed space allocation, UNLOAD PLUS applies MAXPRIM to all of the volumes that you specified in the VOLUMES syntax option or in the installation options module.
Specifying the default
You can specify the default for the MAXPRIM command option in your installation options module by using the MAXPRIM installation option. UNLOAD PLUS was shipped with a default value of 0 for this option. The command option overrides the default that is in the installation options module.
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