Control the GTF on z/OS

Use this topic to understand how to start and stop the z/OS generalized trace facility (GTF).


Starting the GTF

When you start the GTF, specify the USRP option. You are prompted to enter a list of event identifiers (EIDs). The EIDs used by IBM MQ are:

    5E9
    To collect information about control blocks on entry to IBM MQ

    5EA
    To collect information about control blocks on exit from IBM MQ

Sometimes, if an error occurs that we cannot solve yourself, you might be asked by the IBM support center to supply other, internal, trace information for them to analyze. The additional type of trace is:

    5EE
    To collect information internal to IBM MQ

We can also use the JOBNAMEP option, specifying the batch, CICS, IMS, or TSO job name, to limit the trace output to specific jobs. Figure 1 illustrates sample startup for the GTF, specifying the four EIDs, and a jobname. The lines shown in bold type like this are the commands that you enter at the console; the other lines are prompts and responses.

For more information about starting the GTF trace, see the MVS Diagnosis: Tools and Service Aids manual.
Figure 1. Example startup of GTF to use with the IBM MQ trace
START GTFxx.yy
 #HASP100 GTFxx.yy ON STCINRDR
 #HASP373 GTFxx.yy STARTED
*01 AHL100A SPECIFY TRACE OPTIONS
 R 01,TRACE=JOBNAMEP,USRP
 TRACE=JOBNAMEP,USRP
 IEE600I REPLY TO 01 IS;TRACE=JOBNAMEP,USRP
*02 ALH101A SPECIFY TRACE EVENT KEYWORDS - JOBNAME=,USR=
 R 02,JOBNAME=(xxxxMSTR,xxxxCHIN,zzzzzzzz),USR=(5E9,5EA,5EE)
 JOBNAME=(xxxxMSTR,xxxxCHIN,zzzzzzzz),USR=(5E9,5EA,5EE)
 IEE600I REPLY TO 02 IS;JOBNAME=(xxxxMSTR,xxxxCHIN,zzzzzzzz),USR=(5E9,5EA,5EE)
*03 ALH102A CONTINUE TRACE DEFINITION OR REPLY END
 R 03,END
 END
 IEE600I REPLY TO 03 IS;END
 AHL103I TRACE OPTIONS SELECTED-USR=(5E9,5EA,5EE)
 AHL103I JOBNAME=(xxxxMSTR,xxxxCHIN,zzzzzzzz)
*04 AHL125A RESPECIFY TRACE OPTIONS OR REPLY U
 R 04,U
 U
 IEE600I REPLY TO 04 IS;U
 AHL031I GTF INITIALIZATION COMPLETE

where:

     xx is the name of the GTF procedure to use (optional), and yy is an
     identifier for this occurrence of GTF trace.

     xxxx is the name of the queue manager and zzzzzzzz is
     a batch job or CICS region name. Up to 5 job names can be listed.

When using GTF, specify the primary job name (CHINIT, CICS, or batch) in addition to the queue manager name (xxxxMSTR).


Stopping the GTF

When you stop the GTF, we must specify the additional identifier ( yy ) used at startup. Figure 2 illustrates a sample stop command for the GTF. The commands shown in bold type like this are the commands that you enter at the console.
Figure 2. Example of GTF Stop command to use with the IBM MQ trace
 STOP yy
Parent topic: The MQI call and user parameter, and GTF on z/OS


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