This document discusses what the QP0Z* user space objects are on the iSeries.
Resolving The Problem
User Spaces Allocated for Tracing
The XPF TCPIP code uses this mechanism (QP0ZCTRC) for gathering trace information. This mechanism dumps the information into a user space. The idea is for this information to be available for problem analysis. Since V3R2, this has been in place as a form of a flight recorder. In releases after V3R2, FFDC was also added and, for these conditions, spaces were also created. There are some cases where an APAR condition is encountered, and a problem report will be created for the detected condition in addition to the user space that will be created. If an APAR condition was encountered, “WRKPRB” will show that reported condition.
Aside for the APAR reporting condition mentioned above, there is a controlling factor in the generation of the user spaces. If *USRSPC QTOCTCPIP exists in library QUSRSYS, user space with the information will be created. If this space does not exist, the spaces will not be created. If you delete the space, the spaces will not be created.
Some spaces may still be created and not automatically cleaned up. Development indicated they may redesign code for a future release. Until then, these spaces must be cleaned up manually.
Some customers may choose to add the CL command(s) listed below to their IPL startup program as standard course to delete these spaces, if they exist. You should remember to delete the space that controls the creation of the other spaces in QTCP. That is, *USRSPC QTOCTCPIP in QUSRSYS.
To delete the allocated data areas for qtcpip and qtocmonitor jobs, you should issue the following commands:
This same mechanism is in place for the Remote Access (PPP) function. PPP has switched to STRTRC in V5R3 and eliminated these built-in error traces.
Remote Access (PPP)
Unless you are having problems you want to report, you can go ahead and delete the spaces:
Then you can see if there are other jobs besides QTPPPCTL creating traces.
Note: If a client has no need for any of the QP0Z* user space objects in QUSRSYS, the following command can be used to delete them:
18 December 2019