[verse]
*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *enable-channel* option:--kernel
- [option:--discard | option:--overwrite] [option:--output=(`mmap` | `splice`)]
+ [option:--overwrite] [option:--output=(`mmap` | `splice`)]
[option:--subbuf-size='SIZE'] [option:--num-subbuf='COUNT']
[option:--switch-timer='PERIODUS'] [option:--read-timer='PERIODUS']
[option:--tracefile-size='SIZE'] [option:--tracefile-count='COUNT']
[verse]
*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *enable-channel* option:--userspace
- [option:--discard | option:--overwrite] [option:--buffers-pid]
+ [option:--overwrite] [option:--buffers-pid]
[option:--subbuf-size='SIZE'] [option:--num-subbuf='COUNT']
[option:--switch-timer='PERIODUS'] [option:--read-timer='PERIODUS']
+ [option:--blocking-timeout='TIMEOUTUS']
[option:--tracefile-size='SIZE'] [option:--tracefile-count='COUNT']
[option:--session='SESSION'] 'CHANNEL'
For example, consider this command:
[role="term"]
------------------------------------------------------
-lttng enable-channel --kernel --tracefile-size=4096 \
+----
+$ lttng enable-channel --kernel --tracefile-size=4096 \
--tracefile-count=32 my-channel
------------------------------------------------------
+----
Here, for each stream, the maximum size of each trace file is
4 kiB and there can be a maximum of 32 different files. When there is
Target
~~~~~~
-option:-s, option:--session='SESSION'::
+option:-s 'SESSION', option:--session='SESSION'::
Create or enable channel in the tracing session named 'SESSION'
instead of the current tracing session.
* option:--kernel option: {default_kernel_channel_switch_timer}
* `metadata` channel: {default_metadata_switch_timer}
+Timeouts
+~~~~~~~~
+option:--blocking-timeout='TIMEOUTUS'::
+ Set the channel's blocking timeout value to 'TIMEOUTUS' µs
+ for applications executed with a set `LTTNG_UST_ALLOW_BLOCKING`
+ environment variable:
++
+--
+0 (default)::
+ Do not block.
+
+-1::
+ Block forever until room is available in the sub-buffer to write the
+ event record.
+
+__n__, a positive value::
+ Wait for at most __n__ µs when trying to write into a sub-buffer.
+--
+
include::common-cmd-help-options.txt[]
SEE ALSO
--------
man:lttng-disable-channel(1),
-man:lttng(1)
+man:lttng(1),
+man:lttng-ust(3)