JES3 event tracing *MODIFY,E

Function

Use JES3 TRACING to record specific events that occur during JES3 processing. The specific events are described in z/OS JES3 Diagnosis. The trace facility always records trace ids 28 and 29.

An entry will be made in the JES3 event recording trace table unless the JES3 event trace facility has been altered by the *MODIFY,E command.

Note: IATNUC path tracing is always on and cannot be turned off. Only event tracing can be turned off.

Use the *MODIFY,E command to enable, disable, or alter the JES3 event trace facility. This command should only be used as directed by the system programmer.

Except for trace IDs 28 and 29, the *MODIFY,E command is valid for all trace IDs. These trace IDs are always kept active to maintain a record of control flow within JES3.

Syntax


>>-+-*MODIFY-+--,--E--+-,--DISPLAY--------------+--------------><
   '-*F------'        +-,--DUMP--=--+-id--+-----+   
                      |             '-ALL-'     |   
                      +-,--EXCL--=--+-id----+---+   
                      |             '-RESET-'   |   
                      +-,--FIND--=--module name-+   
                      +-,--LIMIT--=--nnn--------+   
                      +-,--OFF------------------+   
                      +-,--ON-------------------+   
                      +-,--START--=--+-PGMCHK-+-+   
                      |              +-RESUME-+ |   
                      |              '-SAT----' |   
                      +-,--STOP--=--+-PGMCHK-+--+   
                      |             +-WAIT---+  |   
                      |             '-SAT----'  |   
                      +-,--SIZE--=--nnn---------+   
                      '-,--TRAP--=--+-address-+-'   
                                    '-RESET---'

Parameters

DISPLAY: Specifies that the trace control data area is to be dumped to the console.
DUMP=id or ALL: Specifies that the designated trace ID entries or all IDs (ALL) are to be dumped to the console. Tracing is suspended for the duration of this dump parameter processing (subject to any limit imposed by LIMIT=). You cannot specify trace ids of 28 or 29.
EXCL=id or RESET: Specifies that the exclusive trace identification designated is to be entered into a queue of exclusive trace IDs. The trace routine only traces the IDs found in this queue. (Each command entered places one ID in the queue; up to ten IDs can be requested.) If RESET is specified, the exclusive trace ID queue is reset. The trace routine resumes tracing on all IDs. You cannot specify trace ids of 28 or 29.
FIND=module name: Locates the entry point of the named module, except for modules in JES3 nucleus or the link pack area (LPA). To locate JES3 nucleus modules or LPA modules, use the *START,DC,FIND=module command.
LIMIT=nn: Limits the number of entries (01 through 99) to be dumped to the operator console. If 00 is specified, a limit of 255 is imposed.
OFF: Specifies that the trace facility is to be disabled.
ON: Specifies that the trace facility is to be enabled.
START=PGMCHK or RESUME: Specifies that the trace facility is to reset the STOP=WAIT condition and force a program interrupt (PGMCHK), or that the trace facility is to post and return control to the calling function (RESUME).
START=SAT: Starts the spool allocation trace.
Note: Trace IDs 120 and 121 are generated with this keyword
STOP=PGMCHK or WAIT: Specifies that any time an ID in the exclusive-ID queue is traced, a X'0C6' program check is to occur in the trace routine, causing an abend of the calling function (PGMCHK) or stopping the calling function (WAIT). If WAIT is specified, other JES3 functions are allowed to continue and the stopped function enters an AWAIT state.
STOP=SAT: Stops the spool allocation trace.
SIZE=nnn: Specifies the trace table size for the trace table indicated on the START= keyword. The default value is 10 MB. If the trace table is allocated in a data space (for example, the SAT trace table), the maximum size allowed is 2,048 MB. If you specify 0, the the service allocates 956 KB unless it is overridden by your installation exit IEFUSI.
TRAP=address or RESET: Specifies that a dynamic trace call be inserted at the address specified. This must be an address within a module in the JES3 address space. The trace call has a fixed ID of one. This command overlays four contiguous bytes at the address specified. The contents of registers 0, 1, 2, 14 and 15 are destroyed.
If RESET is specified, the active trap is reset, and the overlaid instructions are restored if the module is still in virtual storage.