LTTNG-REGENERATE(1)             LTTng Manual             LTTNG-REGENERATE(1)

NAME         top

       lttng-regenerate - Manage an LTTng tracing session's data

SYNOPSIS         top

       Regenerate the metadata of a session:

       lttng [GENERAL OPTIONS] regenerate metadata [--session=SESSION]

       Regenerate the state dump of a session:

       lttng [GENERAL OPTIONS] regenerate statedump [--session=SESSION]

DESCRIPTION         top

       The lttng regenerate command regenerates specific data of a tracing

       As of this version, the metadata and statedump actions are available.

   Regenerating a tracing session’s metadata
       The lttng regenerate metadata action can be used to resample the
       offset between the system’s monotonic clock and the wall-clock time.

       This action is meant to be used to resample the wall-clock time
       following a major NTP
       <> correction. As
       such, a system booting with an incorrect wall time can be traced
       before its wall time is NTP-corrected. Regenerating the tracing
       session’s metadata ensures that trace viewers can accurately
       determine the events time relative to Unix Epoch.

       If you use lttng-rotate(1) or lttng-enable-rotation(1) to make
       tracing session rotations, this action regenerates the current and
       next trace chunks’s metadata files.

   Regenerating a tracing session’s state dump
       The lttng regenerate statedump action can be used to collect
       up-to-date state dump information during the tracing session. This is
       particularly useful in snapshot (see lttng-snapshot(1)) or trace file
       rotation (see lttng-enable-channel(1)) modes where the state dump
       information may be lost.

OPTIONS         top

       General options are described in lttng(1).

       -s SESSION, --session=SESSION
           Regenerate the data of the tracing session named SESSION instead
           of the current 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.

LIMITATIONS         top

       The lttng regenerate metadata command can only be used on kernel and
       user space tracing sessions (using per-user buffering), in non-live

       See lttng-enable-channel(1) for more information about buffering
       schemes and lttng-create(1) for more information about the different
       tracing session modes.


           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

       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

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) command.

           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 <>.
       See the LICENSE <
       tools/blob/master/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

       LTTng-tools is currently maintained by Jérémie Galarneau

SEE ALSO         top


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 2019-05-09.  (At that time,
       the date of the most recent commit that was found in the repository
       was 2019-05-04.)  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-to-
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       manual page), send a mail to

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

Pages that refer to this page: lttng(1)lttng-metadata(1)