BPE-based DBRC trace records
BPE-based DBRC trace records are written to one or more trace tables, and provide information that can help you determine the source of errors.
Trace record eye catchers in a formatted dump provide information about which function resulted in an error. You might be able to correct environmental problems immediately. Refer internal problems to IBM® Software Support with appropriate documentation, such as system console logs and dumps.
BPE-based DBRC trace records are written to one or more of the trace tables shown in the following table.
| Table name | Number of tables | Table description |
|---|---|---|
| ERR | 1 | Used to trace errors that occur within the DBRC address space. Specify as TRCLEV=(ERR,level,DBRC,PAGES=num_pages). The default number of pages for this table is 2. The ERR trace entry is 32-bytes long. |
| GRPS | 1 | Used for DBRC group services messages and notification tracing. Specify as TRCLEV=(GRPS,level,DBRC,PAGES=num_pages). The default number of pages for this table is 8. |
| MODF | N = 1 - 256 | Used for DBRC module flow tracing. Specify as TRCLEV=(MODF,level,DBRC,PAGES=num_pages). The default number of pages for this table is 8. |
| RQST | N = 1 - 256 | Used for general DBRC request processing. Specify as TRCLEV=(RQST,level,DBRC,PAGES=num_pages). The default number of pages for this table is 8. |
Trace entries have the following general format:
0 1 2 3 4 (WD1) 8 (WD2) C (WD3) 10 LL-B LL-1
+---------------------------------------------------------------------------------+
|CD|SC| THD | DTRCALLER | client ID | user data | STCK |
+---------------------------------------------------------------------------------+
- Field name
- Represents
- CD
- 1-byte trace code field that indicates the function that wrote the trace record.
- SC
- 1-byte trace subcode field that indicates the category of the trace record.
- THD
- 2-byte thread sequence number.
- WD1 - WD2
- 2-word trace identifier (DTRCALLR).
- WD3
- The client ID.
- STCK
- 2-word system clock (STCK) that indicates the time when the trace entry was created.
The first four words and the last two words are common fields, and the rest of the information is specific to each entry.
DBRC address space trace records are mapped by macro DSPBDTR.
Trace record mapping is based on the trace subcode, which identifies the category of trace record. One particular trace subcode can apply to many trace codes. Each trace record mapping also includes a pictorial representation in a comment block.
Use the trace subcode to locate the trace record mapping in the DSPBDTR macro. The DSPBCODE macro includes 2-byte module identifier codes that are used in trace records when it is necessary to identify a DBRC module. The module identifier represents the module that wrote the trace record. The DBRC module identifiers are defined in macro DSPBCODE.
The following example shows the format of a 64-byte trace entry (MODF or GRPS trace table):
0 1 2 3 4 8 C 10 14 18 1C 1F
+------------------------------------------------------------+
|CD|SC| THD | WD1 | WD2 | WD3 | WD4 | WD5 | WD6 | WD7 |
+------------------------------------------------------------+
| WD8 | WD9 | WD10 | WD11 | WD12 | WD13 | STCK |
+------------------------------------------------------------+
20 24 28 2C 30 34 38 3F
The following example shows the format of a 128-byte trace entry (RQST trace table):
0 1 2 3 4 8 C 10 14 18 1C 1F
+------------------------------------------------------------+
|CD|SC| THD | WD1 | WD2 | WD3 | WD4 | WD5 | WD6 | WD7 |
+------------------------------------------------------------+
| WD8 | WD9 | WD10 | WD11 | WD12 | WD13 | |
+------------------------------------------------------------+
| |
+------------------------------------------------------------+
| | STCK |
+------------------------------------------------------------+