lttng-clear(1)
-===============
-:revdate: 6 November 2019
+==============
+:revdate: 3 May 2021
NAME
----
-lttng-clear - Clear a tracing session
+lttng-clear - Clear an LTTng tracing session
SYNOPSIS
--------
[verse]
-*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *clear* [option:--all | 'SESSION']
+*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *clear* ['SESSION' | option:--all]
DESCRIPTION
-----------
-The `lttng clear` command clears one or more tracing sessions.
+The `lttng clear` command clears one or more tracing sessions, that is,
+it deletes the contents of their tracing buffers and of all their local
+and streamed trace data.
-If no options are specified, the current tracing session is cleared
-(see man:lttng-create(1) for more information about the current
-tracing session).
+See man:lttng-concepts(7) to learn more about tracing sessions.
-If 'SESSION' is specified, the existing tracing session named 'SESSION'
-is cleared.
+The `clear` command clears:
-If the option:--all option is used, *all* the tracing sessions, as listed
-in the output of `lttng list`, are cleared.
+Without any option::
+ The current tracing session.
++
+See man:lttng-concepts(7) to learn more about the current tracing
+session.
-Clearing a tracing session deletes the contents of the tracing buffers and
-all local or streamed trace data.
+With the 'SESSION' argument::
+ The tracing session named 'SESSION'.
-If a session is configured in snapshot mode, only the tracing buffers are cleared.
+With the option:--all option::
+ *All* the tracing sessions of the connected session daemon for your
+ Unix user, or for all users if your Unix user is `root`, as listed
+ in the output of `lttng list` (see man:lttng-list(1)).
++
+See the ``Session daemon connection'' section of man:lttng(1) to learn
+how a user application connects to a session daemon.
-If at least one rotation occurred, only the tracing buffers and the current
-trace chunks are cleared. Previous trace chunks are not cleared.
+If a tracing session is configured in snapshot mode (see the
+nloption:--snapshot option of the man:lttng-create(1) command), the
+`clear` command only clears the tracing buffers.
-Note that a lttng-relayd daemon can be configured to disallow clear operations
-using LTTNG_RELAYD_DISALLOW_CLEAR. Clear commands performed on a streaming
-session utilizing such lttng-relayd daemon will fail.
+For a given tracing session, if at least one rotation occurred (see
+man:lttng-concepts(7)), the `clear` command only clears its tracing
+buffers and its current trace chunk, :not: its archived trace chunks.
-include::common-cmd-options-head.txt[]
+NOTE: The nloption:--disallow-clear option and the
+`LTTNG_RELAYD_DISALLOW_CLEAR` environment variable of
+man:lttng-relayd(8) can disable remote clearing operations. If LTTng
+sends tracing data over the network for the selected tracing session(s)
+to an LTTng relay daemon configured as such, the `clear` command fails.
+include::common-lttng-cmd-options-head.txt[]
+
+
+Recording target
+~~~~~~~~~~~~~~~~
option:-a, option:--all::
- Clear all tracing sessions.
+ Clear all the tracing sessions of your Unix user, or of all users if
+ your Unix user is `root`, as listed in the output of
+ man:lttng-list(1), instead of the current tracing session or the
+ tracing session named 'SESSION'.
+
+
+include::common-lttng-cmd-help-options.txt[]
+
-include::common-cmd-help-options.txt[]
+include::common-lttng-cmd-after-options.txt[]
-include::common-cmd-footer.txt[]
+include::common-footer.txt[]
SEE ALSO
--------
-man:lttng-rotate(1),
-man:lttng-set-session(1),
-man:lttng(1)
+man:lttng(1),
+man:lttng-create(1),
+man:lttng-concepts(7),
+man:lttng-relayd(8)
projects / lttng-tools.git / blobdiff