Ubuntu Manpage: lttng-load - Load LTTng recording session configurations

NAME

       lttng-load - Load LTTng recording session configurations

SYNOPSIS

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

DESCRIPTION

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

See lttng-concepts(7) to learn more about recording sessions.

Use the load command in conjunction with the lttng-save(1) command to save and restore the
complete configurations of recording sessions. A recording session configuration includes
the enabled channels and recording event rules, the context fields to be recorded, the
recording activity, and more.

Once LTTng loads one or more recording session configurations, they appear exactly as they
were saved from the user’s point of view.

LTTng searches the following directories, non-recursively, in this order for recording
session configuration files:

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

2. /etc/lttng/sessions

Override the input path with the --input-path=PATH option. With this option, LTTng does
NOT search the default directories above. PATH can be the path of one of:

A directory

With the SESSION argument
LTTng searches for the recording session configuration named SESSION in all the
files of the directory PATH and loads it if found.

Without the SESSION argument
The --all option is implicit: LTTng loads all the recording session configurations
found in all the files in the directory PATH.

A file

With the SESSION argument
LTTng searches for the recording session configuration named SESSION in the file
PATH and loads it if found.

Without the SESSION argument
The --all option is implicit: LTTng loads all the recording session configurations
found in the file PATH.

Override the output URL of the loaded recording session configurations with the
--override-url option.

With the SESSION argument, override the name of the loaded recording session configuration
with the --override-name option.

By default, the load command does NOT overwrite existing recording sessions: the command
fails. Allow the load command to overwrite existing recording sessions with the --force
option.

See the “EXAMPLES” section below for usage examples.

OPTIONS

       See lttng(1) for GENERAL OPTIONS.

       -a, --all
           Load all the recording session configurations (default).

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

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

       --override-name=NAME
           Override the name of the loaded recording session configuration, SESSION, with NAME.

       --override-url=URL
           Override the output URL of the loaded recording 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 recording session configurations to load. This
           option applies to all the loaded recording session configurations.

   Program information
       -h, --help
           Show help.

           This option attempts to launch /usr/bin/man to view this manual page. Override the
           manual pager path with the LTTNG_MAN_BIN_PATH environment variable.

       --list-options
           List available command options and quit.

EXIT STATUS

       0
           Success

       1
           Command error

       2
           Undefined command

       3
           Fatal error

       4
           Command warning (something went wrong during the command)

ENVIRONMENT

       LTTNG_ABORT_ON_ERROR
           Set to 1 to abort the process after the first error is encountered.

       LTTNG_HOME
           Path to the LTTng home directory.

           Defaults to $HOME.

           Useful when the Unix user running the commands has a non-writable home directory.

       LTTNG_MAN_BIN_PATH
           Absolute path to the manual pager to use to read the LTTng command-line help (with
           lttng-help(1) or with the --help option) instead of /usr/bin/man.

       LTTNG_SESSION_CONFIG_XSD_PATH
           Path to the directory containing the session.xsd recording session configuration XML
           schema.

       LTTNG_SESSIOND_PATH
           Absolute path to the LTTng session daemon binary (see lttng-sessiond(8)) to spawn from
           the lttng-create(1) command.

           The --sessiond-path general option overrides this environment variable.

FILES

       $LTTNG_HOME/.lttngrc
           Unix user’s LTTng runtime configuration.

           This is where LTTng stores the name of the Unix user’s current recording session
           between executions of lttng(1).  lttng-create(1) and lttng-set-session(1) set the
           current recording session.

       $LTTNG_HOME/lttng-traces
           Default output directory of LTTng traces in local and snapshot modes.

           Override this path with the --output option of the lttng-create(1) command.

       $LTTNG_HOME/.lttng
           Unix user’s LTTng runtime and configuration directory.

       $LTTNG_HOME/.lttng/sessions
           Default directory containing the Unix user’s saved recording session configurations
           (see lttng-save(1) and lttng-load(1)).

       /etc/lttng/sessions
           Directory containing the system-wide saved recording session configurations (see
           lttng-save(1) and lttng-load(1)).

       Note
           $LTTNG_HOME defaults to the value of the HOME environment variable.

EXAMPLES

       Example 1. Load all the recording session configurations from the default search
       directories.

               $ lttng load

       Example 2. Load all the recording session configurations from a specific directory.

           See the --input-path option.

               $ lttng load --input-path=/path/to/sessions

       Example 3. Load a specific recording session configuration from the default search
       directories.

               $ lttng load my-session

       Example 4. Allow LTTng to overwrite existing recording sessions when loading.

           See the --force option.

               $ lttng load --force

       Example 5. Load a specific recording session configuration from a specific file,
       overriding its name.

           See the --input-path and --override-name options.

               $ lttng load my-session --input-path=/path/to/sessions.lttng \
                            --override-name=new-test

RESOURCES

       •   LTTng project website <https://lttng.org>

       •   LTTng documentation <https://lttng.org/docs>

       •   LTTng bug tracker <https://bugs.lttng.org>

       •   Git repositories <https://git.lttng.org>

       •   GitHub organization <https://github.com/lttng>

       •   Continuous integration <https://ci.lttng.org/>

       •   Mailing list <https://lists.lttng.org/> for support and development: lttng-
           dev@lists.lttng.org

       •   IRC channel <irc://irc.oftc.net/lttng>: #lttng on irc.oftc.net

COPYRIGHT

       This program is part of the LTTng-tools project.

       LTTng-tools is distributed under the GNU General Public License version 2
       <http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html>. See the LICENSE
       <https://github.com/lttng/lttng-tools/blob/master/LICENSE> file for details.

THANKS

       Special thanks to Michel Dagenais and the DORSAL laboratory
       <http://www.dorsal.polymtl.ca/> 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.