GDSX Manual

Design and Development
Extended General Device Support (GDSX) Manual–134303
2-83
Modifying the Trace
Opening the Trace File
When the trace facility is turned on in the primary GDSX process without using SCF,
TSCODE allocates an extended segment with segment ID 1025, a default size of 64
pages, and the default file name TRACEP in the subvolume where GDSX is running.
The SCF TRACE command can be used to turn on the trace and specify a different file
name (in which case the file will be created in the subvolume where SCF is running),
and the TSCODE-supported USER^OPEN^TRACE^FILE procedure can be used to
specify a different file size.
When the trace facility is turned on in the backup process without using SCF, TSCODE
allocates an extended segment with segment ID 1025, a default size of 64 pages, and the
file name TRACEB in the subvolume where GDSX is running.
If the specified trace file does not exist, the GDSX process creates and uses the file. If
the default subvolume already has a file with the name specified and the file has not
been opened by another process, the GDSX process opens the file and writes over the
old data. If the specified trace file is in use by any other process, the GDSX process will
not initiate the trace.
Modifying the Trace
During the tracing of a GDSX process, records are added to the trace file until the end of
file is reached. When the end of the file is reached, the trace records wrap to replace the
oldest records in the file, except for the file header. The default for the maximum
number of records that can be generated for the TRACE file before the entries wrap is
4096. Calls to ADD^TRACE^DATA and ADD^TRACE^DATA^INT can change the
maximum number of records that can be generated for the TRACE file before the entries
wrap.
The TRACERECSIZE dynamic configuration parameter specifies the maximum size of
each record added to the trace file. The default for this size is 256 words. The
maximum record size can also be specified in a call to USER^OPEN^TRACE^FILE. If
the record size specified by the TRACERECSIZE configuration parameter differs from
that specified in a call to USER^OPEN^TRACE^FILE, the latter value has precedence.
Once a trace has been initiated, the set of trace classes for which trace records are being
generated can be changed. This is done within USCODE by setting trace^control^flags
or the equivalent DEFINE text. Trace classes cannot be changed within SCF without
first stopping the trace.
SRPOOL SR^POOL^TRACE Traces USCODE pool resources
SRCTRL SR^CTRL^TRACE Traces USCODE controls
SRMISC SR^MISC^TRACE Traces miscellaneous requests from USCODE
USCODE USCODE^TRACE Traces all the above USCODE events
Table 2-7. Events Traced by USAMPLE (page 2 of 2)
SCF Trace
Class Keyword
Equivalent
trace^control^flags
DEFINE USCODE Events Traced by USAMPLE