The following table indicates the parameters you can specify on
a CTnXESxx parmlib member.
| Parameters |
Allowed on CTnXESxx? |
|---|
| ON or OFF |
Yes |
| ASID |
No |
| JOBNAME |
No |
| BUFSIZE |
Yes |
| OPTIONS |
Yes |
| SUB |
Yes, but only for a sublevel trace |
| PRESET |
Yes, but only for a sublevel trace |
| LIKEHEAD |
No |
| WTR |
Yes |
| WTRSTART or WTRSTOP |
Yes |
Setting buffer size: To select a size
for your trace buffers, consider the following:
- The trace buffers can be smaller if you are using an external
writer, because buffer wrapping is not a concern.
- When re-creating a problem, you might first want to make the buffer
size larger.
- SYSXES has one trace buffer of the specified size per
connector, plus one for the global trace. The amount of storage
used can be significant if the system is going to have many connectors.
Furthermore, the trace buffers are allocated from a single common
area data space (CADS). If the entire CADS is used up, subsequent
connections will not be traced because buffer space is not available.
When the BUFSIZE parameter is not specified, SYSXES will allocate
a buffer at the specified size per connector.
- The SYSXES trace buffers are in disabled reference (DREF) data
space storage, so storage constraints may limit buffer size.
Changing buffer size: To change the
size of your trace buffers while a trace is running, either issue
a TRACE CT command or activate a different CTnXESxx parmlib member.
You can use these methods to change SUB levels in the hierarchy so
that different SUB traces can have different sized buffers. The SYSXES
GLOBAL sub buffer size is set by the system to 16MB. You cannot override
this default value.