This topic describes master trace data as it is recorded in the master trace table in the master scheduler address space. You can use this information to write your own formatting or analysis routines for master trace information. Master trace places entries in FIFO order. Thus, a current entry is in front of the older entries. When the table is full, master trace wraps, and resumes recording entries at the end of the table.
Note that the messages may not be in chronological order because the messages may not be put in the master trace table in the order in which they are issued.
You can locate the master trace table from the communication vector table (CVT), as shown in Table 1.
| At the location: | In field: | Find the following address: |
|---|---|---|
| CVT+X'94' | CVTMSER | IEEBASEA (master scheduler resident data area) |
| IEEBASEA+ X'8C' | BAMTTBL | Start of the master trace table |
The unformatted master trace table in the master scheduler address space contains a header and, for each message logged in the table, an entry. The following two topics show the fields in the header and an entry. The master trace table header and entries are mapped by the MTT mappings in the IEEZB806 macro, which can be found in z/OS® MVS™ Data Areas in z/OS Internet library.