This is a Worker startup parameter. Since this parameter is involved in the initial startup of the worker and affects the behavior of the worker before it contacts the supervisor to request a "remote" configuration from the central worker configuration file (see qbwrk.conf), it's considered a bootstrapping parameter and can only be specified in the worker's local qb.conf configuration file. Any of these parameters specified in the global qbwrk.conf file will be ignored.
This is a complete list of the Worker bootstrap parameters
