|
HTML rendering created 2026-09-09 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT | FILES | EXAMPLES | RESOURCES | COPYRIGHT | THANKS | SEE ALSO | COLOPHON |
|
|
|
LTTNG-LIST(1) LTTng Manual LTTNG-LIST(1)
lttng-list - List LTTng recording sessions and instrumentation
points
List the recording sessions:
lttng [GENERAL OPTIONS] list
List the tracing domains of a recording session:
lttng [GENERAL OPTIONS] list --domain SESSION
List the channels and recording event rules of a recording
session:
lttng [GENERAL OPTIONS] list [--channel=CHANNEL] SESSION
[--kernel] [--userspace] [--jul] [--log4j] [--log4j2] [--python]
[--style=(compact | breathe)] [--no-truncate]
[--mem-usage=(total | compact | full)]
List the available LTTng tracepoints, Linux system calls, and/or
Java/Python loggers:
lttng [GENERAL OPTIONS] list
[--kernel [--syscall]] [--userspace [--fields]]
[--jul] [--log4j] [--log4j2] [--python]
The lttng list command lists:
Without arguments
The recording sessions of your Unix user, or of all users if
your Unix user is root, within the connected session daemon.
See the “Session daemon connection” section of lttng(1) to
learn how a user application connects to a session daemon.
The command shows recording session properties such as their
output directories/URLs and whether or not they’re active.
The name of the current recording session is underlined.
With the SESSION argument
With the --domain option
The tracing domains of the recording session named
SESSION.
Without the --domain option
With the --channel=CHANNEL option
The recording event rules of the channel(s) CHANNEL of
the recording session named SESSION.
Without the --channel option
The channels of the recording session named SESSION
and their recording event rules.
By default, the command shows the total memory usage of
each channel. Control the memory usage display mode with
the --mem-usage option.
Use the dedicated tracing domain options (--kernel,
--userspace, --jul, --log4j, --log4j2, and --python) to
only show specific channels.
Without the SESSION argument and with at least one dedicated
tracing domain option
With the --kernel option
Without the --syscall option
The available LTTng kernel tracepoints.
With the --syscall option
The available instrumented Linux system calls.
With the --userspace option
The available LTTng user space tracepoints.
Also list the available instrumentation point fields with
the --fields option.
With the --jul, --log4j, --log4j2, and/or --python options
The available java.util.logging, Apache log4j 1.x, Apache
Log4j 2 and/or Python logger names.
See lttng-concepts(7) to learn more about recording sessions,
tracing domains, channels, recording event rules, and
instrumentation points.
By default, the command adds empty lines between blocks of related
information. Remove those empty lines with the --style=compact
option.
This command shows colored text when the terminal supports it.
Override the terminal coloring behaviour with the LTTNG_TERM_COLOR
and NO_COLOR environment variables.
See the “EXAMPLES” section below for usage examples.
List the channels and recording event rules of the current
recording session (see lttng-concepts(7) to learn more) with the
lttng-status(1) command.
Visual language
The lttng list command uses a structured visual language designed
to make complex tracing configurations easier to read and scan. It
combines terminal colors, Unicode symbols, and indentation to
express hierarchy, state, and metadata.
Color semantics:
┌─────────┬─────────────────────────┐
│ Color │ Meaning │
├─────────┼─────────────────────────┤
│ │ │
│ Green │ Enabled, active, or │
│ │ valid items. │
├─────────┼─────────────────────────┤
│ │ │
│ Red │ Disabled, inactive, or │
│ │ invalid items. │
├─────────┼─────────────────────────┤
│ │ │
│ Cyan │ Important object nodes: │
│ │ recording sessions, │
│ │ tracing domains, │
│ │ channels, and event │
│ │ rules. │
│ │ │
│ │ Those nodes act as │
│ │ section headers. │
├─────────┼─────────────────────────┤
│ │ │
│ Yellow │ Metadata such as counts │
│ │ and timestamps. │
├─────────┼─────────────────────────┤
│ │ │
│ Magenta │ Warning information. │
└─────────┴─────────────────────────┘
Symbolic conventions:
┌─────────┬──────────────────────────┐
│ Symbol │ Meaning │
├─────────┼──────────────────────────┤
│ │ │
│ • and ◼ │ Active/inactive │
│ │ recording session. │
├─────────┼──────────────────────────┤
│ │ │
│ ✓ and × │ Enabled/disabled channel │
│ │ or event rule. │
├─────────┼──────────────────────────┤
│ │ │
│ 🞂 │ Attribute or attribute │
│ │ group. │
├─────────┼──────────────────────────┤
│ │ │
│ ┆ │ Vertical continuation. │
└─────────┴──────────────────────────┘
See lttng(1) for GENERAL OPTIONS.
Tracing domain
-j, --jul
Without the SESSION argument
List the java.util.logging logger names.
With the SESSION argument
Only list the java.util.logging recording event rules.
-k, --kernel
Without the SESSION argument
List the LTTng kernel instrumentation points.
With the SESSION argument
Only list the Linux kernel channels and their recording
event rules.
-l, --log4j
Without the SESSION argument
List the Apache log4j 1.x logger names.
With the SESSION argument
Only list the Apache log4j 1.x recording event rules.
--log4j2
Without the SESSION argument
List the Apache Log4j 2 logger names.
With the SESSION argument
Only list the Apache Log4j 2 recording event rules.
-p, --python
Without the SESSION argument
List the Python logger names.
With the SESSION argument
Only list the Python recording event rules.
-u, --userspace
Without the SESSION argument
List the LTTng user space tracepoints.
With the SESSION argument
Only list the user space channels and their recording
event rules.
Filtering
-c CHANNEL, --channel=CHANNEL
Only list the properties and recording event rules of the
channel(s) named CHANNEL.
Only available with the SESSION argument.
-d, --domain
Show the tracing domains of the recording session named
SESSION.
-f, --fields
When listing user space tracepoints, also show their fields if
they’re available.
--syscall
When listing LTTng kernel instrumentation points, only list
Linux system calls.
Display
--mem-usage=MODE
Set the channel memory usage display mode to MODE.
MODE is one of:
total (default)
Show the total memory usage of the channel.
compact
Show the memory usage for each Unix user or process,
depending on the buffer ownership model of the channel
(see the --buffer-ownership option of
lttng-enable-channel(1)).
full
Show the memory usage for each CPU (if available).
Only available with the SESSION argument.
--no-truncate
Do NOT truncate long output lines.
By default, the command truncates lines, adding an ellipsis,
to fit the current terminal width.
--style=STYLE
Set the command output style to STYLE.
STYLE is one of:
breathe (default)
Add empty lines to make blocks of related information
stand out.
compact
Make the the output compact.
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.
0
Success
1
Command error
2
Undefined command
3
Fatal error
4
Command warning (something went wrong during the command)
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_LIST_LEGACY
Set to 1 to use the legacy output format (LTTng 2.14 and
earlier) for the lttng-list(1) command instead of the modern
output format.
Note that the legacy output doesn’t show anything related to
features introduced after LTTng 2.14.
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_NO_UTF_8
Set to 1 to NOT emit multi-byte UTF-8 sequences, even if the
locale claims to support it.
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.
LTTNG_TERM_COLOR
Controls when to emit terminal SGR codes in the output.
The NO_COLOR environment variable overrides this.
One of:
auto (default)
Only emit SGR codes when the standard output is connected
to a color-capable terminal.
always
Always emit SGR codes.
never
Never emit SGR codes.
NO_COLOR
If set and not empty, then it’s equivalent to setting
LTTNG_TERM_COLOR to never.
See NO_COLOR <https://no-color.org/> to learn more.
$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)).
/usr/local/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.
Example 1. List the recording sessions.
$ lttng list
Example 2. Show the details of a specific recording session.
$ lttng list my-session
Example 3. List the available Linux kernel system call
instrumentation points.
$ lttng list --kernel --syscall
Example 4. List the available user space tracepoints with their
fields.
See the --fields option.
$ lttng list --userspace --fields
Example 5. List the tracing domains of a specific recording
session having at least one channel.
See the --domain option.
$ lttng list --domain my-session
Example 6. Show the details of a specific channel, including its
current data stream infos, in a specific recording session.
See the --channel option.
$ lttng list my-session --channel=channel0 --stream-info-details
• 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
• Mastodon <https://mastodon.social/@lttng>
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.
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.
lttng(1), lttng-concepts(7)
This page is part of the LTTng-Tools (LTTng tools) project.
Information about the project can be found at ⟨http://lttng.org/⟩.
It is not known how to report bugs for this man page; if you know,
please send a mail to man-pages@man7.org. This page was obtained
from the project's upstream Git repository
⟨https://github.com/lttng/lttng-tools.git⟩ on 2026-08-04. (At
that time, the date of the most recent commit that was found in
the repository was 2026-07-30.) 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
man-pages@man7.org
LTTng 2.15.1 2 December 2025 LTTNG-LIST(1)
Pages that refer to this page: lttng(1), lttng-add-context(1), lttng-add-trigger(1), lttng-clear(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-list-triggers(1), lttng-load(1), lttng-metadata(1), lttng-reclaim-memory(1), lttng-regenerate(1), lttng-remove-trigger(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-ust(3), lttng-concepts(7), lttng-event-rule(7)
|
HTML rendering created 2026-09-09 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|