Use User index range (-userindexrangesize) to specify the number of rows maintained in the_UserIndexStat VST.

Operating system and syntax UNIX / Windows 
-userindexrangesize n
Use with Maximum value Minimum value Single-user default Multi-user default
Database Server, Client Connection 65536 256 256 256
n
The number of user indexes for which you want gather information in the _UserIndexStat VST.
Note: If the User index base and range are not specified, the _UserIndexStat VST is dimensioned using the values specified for the _IndexStat VST (-baseindex and -indexrangesize).

The User Index Range (-userindexrangesize) parameter may be modified while your database is online using PROUTIL INCREASETO. The new value should be set greater than the current value. In the event there is insufficient shared memory for the new increased -userindexrangesize value, an additional shared memory segment will be added. If there are existing connections, the utility will keep asking to retry until all the existing connections recognize the new segment.