Application environments can be manually controlled by the installation or automatically controlled by workload management. Note, however, that Dynamic Application Environments can only be automatically controlled by workload management. All of the applications in an application environment are supported by a single JCL startup procedure. Defining the name of this startup JCL procedure to workload management indicates that workload management should control the server address spaces. This is called automatic control. If you omit the name of the JCL procedure in the application environment definition, then manual control is in effect.
Under manual control, the installation must create and delete, as needed, the server address spaces for each application environment. Note that the VARY WLM,APPLENV command can be used to terminate manually started server address spaces (through the quiesce or refresh options), but it will not restart them. For more information on the VARY WLM,APPLENV command, see Using operator commands for application environments.
Under automatic control, workload management creates server address spaces as started tasks using the JCL procedure specified in the application environment definitions. The startup parameters may be contained in either the JCL procedure defined for each application environment or in the application environment definition. When the server address spaces are no longer needed, workload management deletes them.