lttng-load(1) — Linux manual page


LTTNG-LOAD(1)                 LTTng Manual                 LTTNG-LOAD(1)

NAME         top

       lttng-load - Load LTTng tracing session configurations

SYNOPSIS         top

       lttng [GENERAL OPTIONS] load [--force] [--input-path=PATH]
             [--override-url=URL] [SESSION [--override-name=NAME]]

DESCRIPTION         top

       The lttng load command loads the configurations of one or more
       tracing sessions from files.

       The lttng load command is used in conjunction with the
       lttng-save(1) command to save and restore the complete
       configurations of tracing sessions. This includes the enabled
       channels and event rules, the context added to channels, the
       tracing activity, and more.

       Once one or more tracing session configurations are loaded, they
       appear exactly as they were saved from the user’s point of view.

       The following directories are searched, non-recursively, in this
       order for configuration files:

        1. $LTTNG_HOME/.lttng/sessions ($LTTNG_HOME defaults to $HOME)

        2. /usr/local/etc/lttng/sessions

       The input path can be overridden with the --input-path option.
       When this option is specified, the default directories are NOT
       searched for configuration files. When it’s not specified, both
       default directories are searched for configuration files.

       If the input path is a directory, then:

       •   If SESSION is specified, the tracing session configuration
           named SESSION is searched for in all the files of this
           directory and loaded if found.

       •   If SESSION is not specified, the --all option is implicit:
           all the tracing session configurations found in all the files
           in this directory are loaded.

       If the input path is a file, then:

       •   If SESSION is specified, the tracing session configuration
           named SESSION is searched for in this file and loaded if

       •   If SESSION is not specified, the --all option is implicit:
           all the tracing session configurations found in this file are

       Aspects of the loaded configurations can be overridden at load
       time using the --override-url and --override-name options.

       By default, existing tracing sessions are not overwritten when
       loading: the command fails. The --force option can be used to
       allow this.

OPTIONS         top

       General options are described in lttng(1).

       -a, --all
           Load all tracing session configurations (default).

       -f, --force
           Overwrite existing tracing sessions when loading.

       -i PATH, --input-path=PATH
           Load tracing session configurations from PATH, either a
           directory or a file, instead of loading them from the default
           search directories.

           Override the name of the loaded tracing session
           configuration, SESSION, with NAME.

           You must specify a tracing session name to load (SESSION) and
           NOT use the --all option when using this option.

           Override the URL of the loaded tracing session configurations
           with URL.

           This is the equivalent of the --set-url option of
           lttng-create(1). The validity of the URL override depends on
           the type of tracing session configurations to load. This
           option applies to all the loaded tracing session

   Program information
       -h, --help
           Show command help.

           This option, like lttng-help(1), attempts to launch
           /usr/bin/man to view the command’s man page. The path to the
           man pager can be overridden by the LTTNG_MAN_BIN_PATH
           environment variable.

           List available command options.


           Set to 1 to abort the process after the first error is

           Overrides the $HOME environment variable. Useful when the
           user running the commands has a non-writable home directory.

           Absolute path to the man pager to use for viewing help
           information about LTTng commands (using lttng-help(1) or
           lttng COMMAND --help).

           Path in which the session.xsd session configuration XML
           schema may be found.

           Full session daemon binary path.

           The --sessiond-path option has precedence over this
           environment variable.

       Note that the lttng-create(1) command can spawn an LTTng session
       daemon automatically if none is running. See lttng-sessiond(8)
       for the environment variables influencing the execution of the
       session daemon.

FILES         top

           User LTTng runtime configuration.

           This is where the per-user current tracing session is stored
           between executions of lttng(1). The current tracing session
           can be set with lttng-set-session(1). See lttng-create(1) for
           more information about tracing sessions.

           Default output directory of LTTng traces. This can be
           overridden with the --output option of the lttng-create(1)

           User LTTng runtime and configuration directory.

           Default location of saved user tracing sessions (see
           lttng-save(1) and lttng-load(1)).

           System-wide location of saved tracing sessions (see
           lttng-save(1) and lttng-load(1)).


           $LTTNG_HOME defaults to $HOME when not explicitly set.

EXIT STATUS         top


           Command error

           Undefined command

           Fatal error

           Command warning (something went wrong during the command)

BUGS         top

       If you encounter any issue or usability problem, please report it
       on the LTTng bug tracker <

RESOURCES         top

       •   LTTng project website <>

       •   LTTng documentation <>

       •   Git repositories <>

       •   GitHub organization <>

       •   Continuous integration <>

       •   Mailing list <> for support and

       •   IRC channel <irc://>: #lttng on

COPYRIGHTS         top

       This program is part of the LTTng-tools project.

       LTTng-tools is distributed under the GNU General Public License
       version 2 <
       licenses/gpl-2.0.en.html>. See the LICENSE
       <> file
       for details.

THANKS         top

       Special thanks to Michel Dagenais and the DORSAL laboratory
       <> at École Polytechnique de
       Montréal for the LTTng journey.

       Also thanks to the Ericsson teams working on tracing which helped
       us greatly with detailed bug reports and unusual test cases.

AUTHORS         top

       LTTng-tools was originally written by Mathieu Desnoyers, Julien
       Desfossez, and David Goulet. More people have since contributed
       to it.

       LTTng-tools is currently maintained by Jérémie Galarneau

SEE ALSO         top

       lttng-save(1), lttng(1)

COLOPHON         top

       This page is part of the LTTng-Tools (    LTTng tools) project.
       Information about the project can be found at 
       ⟨⟩.  It is not known how to report bugs for this
       man page; if you know, please send a mail to
       This page was obtained from the project's upstream Git repository
       ⟨git://⟩ on 2019-11-19.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2019-11-14.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

LTTng 2.12.0-pre               10/29/2018                  LTTNG-LOAD(1)

Pages that refer to this page: lttng(1)lttng-add-context(1)lttng-calibrate(1)lttng-create(1)lttng-destroy(1)lttng-disable-channel(1)lttng-disable-event(1)lttng-disable-rotation(1)lttng-enable-channel(1)lttng-enable-event(1)lttng-enable-rotation(1)lttng-help(1)lttng-list(1)lttng-load(1)lttng-metadata(1)lttng-regenerate(1)lttng-rotate(1)lttng-save(1)lttng-set-session(1)lttng-snapshot(1)lttng-start(1)lttng-status(1)lttng-stop(1)lttng-track(1)lttng-untrack(1)lttng-version(1)lttng-view(1)lttng-sessiond(8)