CETR - trace control

Use CETR to control CICS tracing activity.

To start the transaction, type CETR on the command line, then press Enter.

The following screen is displayed, with values from your system in each field. You can overtype any input field with the new values that you require. When you press Enter, CETR issues the necessary commands to set the new values. If there are any errors, press PF9 to display the error messages. If there is only one short error message, it appears near the bottom of this display.

Figure 1. CETR transaction: initial screen
 CETR                    CICS Trace Control Facility           

 Type in your choices.

 Item                              Choice       Possible choices

 Internal Trace Status       ===>  STOPPED      STArted, STOpped
 Internal Trace Table Size   ===>  16      K    16K - 1048576K

 Auxiliary Trace Status      ===>  PAUSED       STArted, STOpped, Paused
 Auxiliary Trace Data Set     ===>  B            A, B
 Auxiliary Switch Status     ===>  ALL          NO, NExt, All

 GTF Trace Status            ===>  STARTED      STArted, STOpped

 Master System Trace Flag    ===>  OFF          ON, OFf
 Master User Trace Flag      ===>  OFF          ON, OFf

 When finished, press ENTER.




 PF1=Help    3=Quit    4=Components    5=Ter/Trn    6=Pooled JVMs    9=Error List

Trace field descriptions

In the example screen, the fields are as follows:
  • The internal trace status is STOPPED, so regular tracing is not directed explicitly to the internal trace table. However, the internal trace table is used as a buffer for the other trace destinations, so it always contains the most recent trace entry if at least one trace destination is STARTED.

    The internal trace table is also used as a destination for exception trace entries, which are made whenever CICS detects an exception condition. If an exception condition is detected when the options shown in this example are set, you would find the exception trace entry in the internal trace table as well as in the GTF trace data set.

  • The internal trace table size is 16 KB, which is the minimum size. If the internal trace status was STARTED, the trace table would wrap when it became full.

    If you change the size of the internal trace table, check your current setting for the z/OS parameter MEMLIMIT. MEMLIMIT limits the amount of 64-bit storage that the CICS address space can use. Your setting for TRTABSZ must remain within MEMLIMIT, and you must also allow for other use of 64-bit storage in the CICS region.

    For more information about storage use for the internal trace table, see CICS trace: performance and tuning.
  • The current auxiliary trace data set is B, meaning that trace entries are written to DFHBUXT if auxiliary tracing is started. As its status is shown to be PAUSED, no tracing is done to that destination. The auxiliary switch status is ALL, so a switch would be made to the other auxiliary trace data set whenever one became full.
  • The GTF trace status is shown to be STARTED, which means that CICS trace entries are written to the GTF trace data set defined to MVS. To write trace entries to GTF, GTF tracing must be started under MVS with the TRACE=USR option.

    If the CICS GTF status is started, but GTF tracing has not been started under MVS, trace entries are not written. In this situation, no error condition is reported.

  • The master system trace flag is OFF. This means that no standard tracing is done at all, even though standard tracing might be specified for some tasks. However, special task tracing is not affected. The master system trace flag only determines whether standard task tracing is to be done.
CETR also provides the following functions:
  • Set the component trace options (press PF4)
  • Set the transaction and terminal trace options (press PF5)
  • Set the JVM trace options (press PF6)

For information about the use of the various CETR options as an aid to problem determination, see Using traces in problem determination.