Automatic decompression of objects

Compressed objects shipped in the IBM® i or other IBM licensed programs are decompressed by the system after the licensed programs are installed.

The decompression occurs only when sufficient storage is available on the system.

System jobs called QDCPOBJx are automatically started by the system to decompress objects.

The number of QDCPOBJ jobs is based on number of processors + 1. The jobs are system jobs running at priority 60 which can't be changed, ended or held by the user. A QDCPOBJx job may be in one of the following statuses, which are from the Work Active Job (WRKACTJOB) command:

RUN (running): The job is actively decompressing objects.
EVTW (event wait): The job is not actively decompressing objects. The job is active in case more objects need to be decompressed (that is additional licensed programs are installed).
DLYW (delay wait): The job is temporarily halted. The following situations could cause the QDCPOBJx jobs to halt:
- The system is running in restricted state (that is ENDSYS or ENDSBS *ALL was issued)
- A licensed program was just installed from the "Work with Licensed Programs" display. The job is in a delay wait state for a maximum of 15 minutes before starting to decompress objects.
LCKW (lock wait): The job is waiting for an internal lock. Typically, this occurs when one QDCPOBJ job is in DLYW state.

The following storage requirements apply if the operating system was installed over an existing operating system:

The system must have greater than 250 megabytes of unused storage for the QDCPOBJx jobs to start.
On a system with available storage of greater than 750MB, the jobs are submitted to decompress all system objects just installed.
On a system with available storage of less than 250MB, jobs are not submitted, and the objects are decompressed as they are used.
On a system with available storage between 250MB and 750MB, only frequently-used objects are automatically decompressed.

Frequently-used objects are objects that have been used at least five times and the last use was within the last 14 days. The remaining low-use objects remain compressed.

The system must have greater than 1000MB of unused storage if the operating system is installed on a system that has been initialized using options 2, Install Licensed Internal Code and Initialize the system, from the Install Licensed Internal Code (LIC) display.

If QDCPOBJx jobs are active at the last system termination, the jobs are started again at the time of the next IPL.