Trace Output Datasets
Details about how datasets can be used to store output from the trace facility are explained in this section.
Trace Datasets Must Exist
The trace datasets are disk datasets that must exist before the trace facility is started. If an attempt is made to use a dataset that doesn’t exist, the trace destination will go into “mute” mode. A message will be issued via WTO to the system log, indicating that the dataset allocation failed. No trace data will be recorded until a dataset is allocated and either the server is stopped and started, or refreshed, or a Trace Data Set Switch is issued from M.SM.
Trace Dataset Allocation
The trace datasets are allocated with DISP=SHR to allow them to be browsed while the data is still being generated.
Since the trace facility uses QSAM (which is buffered), the last few trace messages will probably still be in a memory buffer at any given time.
Trace Dataset Attributes
Any trace datasets that are allocated should have the following attributes:
- DSORG=PS
- LRECL=132
- BLKSIZE=8184
- RECFM=FB
They will be set when the dataset is used.
Default Trace Dataset Names
The names of the default datasets that ISPW expects to find are:
- 'ISPW.ISPW.LOGA'
- 'ISPW.ISPW.DEBUGA'
If either dataset doesn’t exist, a message will be sent to the system log indicating that tracing has not been started.
A different dataset name can be specified on the appropriate trace destination card in the SDEFISPW file or on the M.SM panel for a Data Set Switch.