lttng-clear(1)
===============
:revdate: 6 November 2019

NAME
----
lttng-clear - Clear a tracing session


SYNOPSIS
--------
[verse]
*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *clear* [option:--all | 'SESSION']


DESCRIPTION
-----------
The `lttng clear` command clears one or more tracing sessions.

If no options are specified, the current tracing session is cleared
(see man:lttng-create(1) for more information about the current
tracing session).

If 'SESSION' is specified, the existing tracing session named 'SESSION'
is cleared.

If the option:--all option is used, *all* the tracing sessions, as listed
in the output of `lttng list`, are cleared.

Clearing a tracing session deletes the contents of the tracing buffers and
all local or streamed trace data.

If a session is configured in snapshot mode, only the tracing buffers are cleared.

If at least one rotation occurred, only the tracing buffers and the current
trace chunks are cleared. Previous trace chunks are not cleared.

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.

include::common-cmd-options-head.txt[]


option:-a, option:--all::
    Clear all tracing sessions.

include::common-cmd-help-options.txt[]


include::common-cmd-footer.txt[]


SEE ALSO
--------
man:lttng-rotate(1),
man:lttng-set-session(1),
man:lttng(1)