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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT | FILES | EXAMPLES | RESOURCES | COPYRIGHT | THANKS | SEE ALSO | COLOPHON |
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LTTNG-ENABLE-ROTAT(1) LTTng Manual LTTNG-ENABLE-ROTAT(1)
lttng-enable-rotation - Set an LTTng recording session rotation
schedule
lttng [GENERAL OPTIONS] enable-rotation [--session=SESSION]
(--timer=PERIODUS | --size=SIZE | --timer=PERIODUS --size=SIZE)
The lttng enable-rotation command sets a recording session
rotation schedule for:
With the --session=SESSION option
The recording session named SESSION.
Without the --session option
The current recording session (see lttng-concepts(7) to learn
more about the current recording session).
See lttng-concepts(7) to learn more about the recording session
rotation and trace chunk concepts.
With the --timer=PERIODUS option, the enable-rotation command sets
a rotation schedule so that LTTng performs an automatic rotation
at least every PERIODUS.
With the --size=SIZE option, the enable-rotation command sets a
rotation schedule so that LTTng performs an automatic rotation
every time the total size of the flushed part of the current trace
chunk is at least SIZE.
For both the --timer and --size options, LTTng checks the schedule
condition periodically using the monitor timers of the channels of
the selected recording session (see the --monitor-timer option of
the lttng-enable-channel(1) command). This means that:
• With the --timer=PERIODUS option, LTTng can perform an
automatic rotation when the elapsed time since the last
automatic rotation is slightly greater than PERIODUS.
The exact precision depends on the precision of the monitor
timer, which relies on the precision of the platform
implementation of POSIX timers.
• With the --size=SIZE option, LTTng can perform an automatic
rotation when the size of the flushed part of the current
trace chunk is greater than SIZE.
You may combine the --timer and --size options.
See the lttng-concepts(7) to learn how LTTng names a trace chunk
archive directory.
See the “EXAMPLES” section below for usage examples.
Unset a recording session rotation schedule with the
lttng-disable-rotation(1) command.
Important
You may only use the enable-rotation command when all of the
following conditions are true:
• The selected recording session was created in normal mode
or in network streaming mode (see lttng-create(1)).
• No channel was created with a configured trace file count
or size limit (see the --tracefile-size and --tracefile-
count options of the lttng-enable-channel(1) command).
For a given recording session, LTTng only performs an
automatic rotation when it’s not currently performing a
rotation.
See lttng(1) for GENERAL OPTIONS.
Rotation schedule condition
--size=SIZE
Set a rotation schedule so that LTTng performs an automatic
rotation every time the total size of the flushed part of the
current trace chunk is at least SIZE bytes.
The k (KiB), M (MiB), and G (GiB) suffixes are supported.
--timer=PERIODUS
Set a rotation schedule so that LTTng performs an automatic
rotation approximately every PERIODUS microseconds.
The ms (milliseconds), s (seconds), m (minutes), and h (hours)
suffixes are supported.
Recording target
-s SESSION, --session=SESSION
Set a rotation schedule for the recording session named
SESSION instead of the current recording session.
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. Set the size-based rotation schedule of the current
recording session.
See the --size option.
$ lttng disable-rotation --size=256M
Example 2. Set the periodic rotation schedule of a specific
recording session.
See the --timer and --session options.
$ lttng disable-rotation --session=my-session --timer=5m
• 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-create(1), lttng-disable-rotation(1),
lttng-rotate(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 14 June 2021 LTTNG-ENABLE-ROTAT(1)
Pages that refer to this page: lttng(1), lttng-disable-rotation(1), lttng-rotate(1), lttng-concepts(7)
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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. |
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