lttng-list — List LTTng tracing sessions, domains, channels, and events
Synopsis
List existing tracing sessions:
lttng [GENERAL OPTIONS] list
List available event sources:
lttng [GENERAL OPTIONS] list [--fields]
[--kernel [--syscall]] [--userspace] [--jul] [--log4j] [--python]
List tracing session’s domains:
lttng [GENERAL OPTIONS] list --domain SESSION
List tracing session’s channels and event rules:
lttng [GENERAL OPTIONS] list [--channel=CHANNEL] SESSION
Description
The lttng list command lists tracing sessions, tracing domains, channels, and events.
Without arguments, lttng list lists the existing tracing sessions and shows if they are active or not.
With one or more of the --kernel, --userspace, --jul, --log4j, and --python domain options, the command lists the available event sources of the selected domain on the system. The JUL, log4j, and Python domains list the names of their available loggers. The --syscall option can be used alongside the --kernel option to get a list of traceable Linux system calls. The --fields option can be used to show the fields of the listed event sources.
Providing a tracing session name SESSION targets a specific tracing session. If the --domain option is used, domains containing at least one channel in the selected tracing session are listed. Otherwise, all the domains, channels, and event rules of the selected tracing session are listed along with its details (trace path, for example), except when the --channel option is used to isolate a specific channel by name.
Options
General options are described in lttng(1).
Domain
- -j, --jul
List event sources in the java.util.logging (JUL) domain.
- -k, --kernel
List event sources in the Linux kernel domain.
- -l, --log4j
List event sources in the Apache log4j domain.
- -p, --python
List event sources in the Python domain.
- -u, --userspace
List event sources in the user space domain.
Target
- -c CHANNEL, --channel=CHANNEL
Only list the details of the channel named CHANNEL.
Listing
- -d, --domain
Show the domains of the target tracing session in which at least one channel exists.
- -f, --fields
When listing the event sources with one of the domain options, also show their fields.
- --syscall
When listing the event sources of the Linux kernel domain, list the traceable system calls instead of the kernel tracepoints.
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-options
List available command options.
Environment Variables
- LTTNG_ABORT_ON_ERROR
Set to 1 to abort the process after the first error is encountered.
- LTTNG_HOME
Overrides the $HOME environment variable. Useful when the user running the commands has a non-writable home directory.
- LTTNG_MAN_BIN_PATH
Absolute path to the man pager to use for viewing help information about LTTng commands (using lttng-help(1) or lttng COMMAND --help).
- LTTNG_SESSION_CONFIG_XSD_PATH
Path in which the session.xsd session configuration XML schema may be found.
- LTTNG_SESSIOND_PATH
-
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
- $LTTNG_HOME/.lttngrc
-
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.
- $LTTNG_HOME/lttng-traces
Default output directory of LTTng traces. This can be overridden with the --output option of the lttng-create(1) command.
- $LTTNG_HOME/.lttng
User LTTng runtime and configuration directory.
- $LTTNG_HOME/.lttng/sessions
Default location of saved user tracing sessions (see lttng-save(1) and lttng-load(1)).
- /usr/local/etc/lttng/sessions
System-wide location of saved tracing sessions (see lttng-save(1) and lttng-load(1)).
Note
$LTTNG_HOME defaults to $HOME when not explicitly set.
Exit Status
- 0
Success
- 1
Command error
- 2
Undefined command
- 3
Fatal error
- 4
Command warning (something went wrong during the command)
Bugs
If you encounter any issue or usability problem, please report it on the LTTng bug tracker <https://bugs.lttng.org/projects/lttng-tools>.
Resources
- LTTng project website <https://lttng.org>
- LTTng documentation <https://lttng.org/docs>
- Git repositories <http://git.lttng.org>
- GitHub organization <http://github.com/lttng>
- Continuous integration <http://ci.lttng.org/>
- Mailing list <http://lists.lttng.org> for support and development: lttng-dev@lists.lttng.org
- IRC channel <irc://irc.oftc.net/lttng>: #lttng on irc.oftc.net
Copyrights
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.
See Also
Referenced By
lttng(1), lttng-destroy(1), lttng-enable-channel(1), lttng-enable-event(1), lttng-save(1), lttng-set-session(1), lttng-start(1), lttng-stop(1), lttng-ust(3), lttng-view(1).