Default Activation Groups

When a job is started, the system creates two activation groups to be used by all OPM programs. One of these activation groups is used for application programs. The other is used for operating system programs. These OPM default activation groups use single-level storage for static program variables. You cannot delete the OPM default activation groups. They are deleted by the system when your job ends.

ILE programs and service programs can be activated in the OPM default activation groups if the following conditions are satisfied:

  • The ILE programs or service programs were created with the activation group *CALLER option or with the DFTACTGRP(*YES) option.
    Note: The DFTACTGRP(*YES) option is only available on the CRTBNDCL (ILE CL) and CRTBNDRPG (ILE RPG) commands.
  • The call to the ILE programs or service programs originates in the OPM default activation groups.
  • The ILE program or service program does not use the teraspace storage model.
The operating system will also create a teraspace default activation group when it determines one is needed. The teraspace default activation group uses teraspace storage for static program variables. You cannot delete the teraspace default activation group. It will be deleted by the system when your job ends. ILE programs and service programs can be activated in the teraspace default activation group if the following conditions are satisfied:
  • The ILE program or service program was created with the activation group *CALLER option.
  • The state of the ILE program or service program is *USER.
One of the following conditions must also be satisfied for the ILE program or service program to be activated into the teraspace default activation group:
  • The call to the ILE program or service program originates in the teraspace default activation group and the ILE program or service program was created with either the storage model *INHERIT or the storage model *TERASPACE option.
  • The ILE program or service program was created with the storage model *INHERIT option, there are no application entries on the call stack associated with a different activation group, and the activation occurs in preparation for one of these invocations:
    • SQL stored procedure
    • SQL function
    • SQL trigger
    Note: Starting with IBM® i 7.1, SQL procedures, functions and triggers are created with storage model *INHERIT. On previous releases, SQL procedures, functions, and triggers were created with storage model *SNGLVL.
  • The ILE program or service program was created with the storage model *TERASPACE option and there are no call stack entries associated with a teraspace storage model activation group. See Selecting a Compatible Activation Group for additional information.

The static and heap storage used by ILE programs activated in one of the default activation groups are not returned to the system until the job ends. Similarly, temporary data management resources associated with any default activation group are normally scoped to a job. For example, normally, open files are not closed by the system until the job ends; see Reclaim Resources Command for ILE Programs for more information.