When global buffers are enabled, the NUMBER IS clause is used to
    specify the default number of global buffers per node.

    The default number of global buffers is the maximum number
    of users multiplied by 5. (In the RDO syntax for database
    parameters, a user is the same as an attach.) You can override
    the default by defining a value for the logical name RDM$BIND_
    BUFFERS.

    Although you can change the NUMBER IS parameter online, the
    change will only take effect the next time that the database is
    opened. By default, a database can be opened automatically (that
    is, by any user who invokes the database and executes a data
    manipulation language statement). If the database was modified
    so that it must be manually opened, the RMU/OPEN command must be
    used to open it.