1LTTNG-REGENERATE(1) LTTng Manual LTTNG-REGENERATE(1)
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6 lttng-regenerate - Manage an LTTng tracing session's data regeneration
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9 Regenerate the metadata of a session:
10 lttng [GENERAL OPTIONS] regenerate metadata [--session=SESSION]
12 Regenerate the state dump of a session:
14 lttng [GENERAL OPTIONS] regenerate statedump [--session=SESSION]
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18 The lttng regenerate command regenerates specific data of a tracing
19 session.
20 As of this version, the metadata and statedump actions are available.
22 Regenerating a tracing session’s metadata
24 The lttng regenerate metadata action can be used to resample the offset
25 between the system’s monotonic clock and the wall-clock time.
26 This action is meant to be used to resample the wall-clock time
28 following a major NTP
29 <https://en.wikipedia.org/wiki/Network_Time_Protocol> correction. As
30 such, a system booting with an incorrect wall time can be traced before
31 its wall time is NTP-corrected. Regenerating the tracing session’s
32 metadata ensures that trace viewers can accurately determine the events
33 time relative to Unix Epoch.
34 Regenerating a tracing session’s state dump
36 The lttng regenerate statedump action can be used to collect up-to-date
37 state dump information during the tracing session. This is particularly
38 useful in snapshot (see lttng-snapshot(1)) or trace file rotation (see
39 lttng-enable-channel(1)) modes where the state dump information may be
40 lost.
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43 General options are described in lttng(1).
44 -s SESSION, --session=SESSION
46 Regenerate the data of the tracing session named SESSION instead of
47 the current tracing session.
48 Program information
50 -h, --help
51 Show command help.
52 This option, like lttng-help(1), attempts to launch /usr/bin/man to
54 view the command’s man page. The path to the man pager can be
55 overridden by the LTTNG_MAN_BIN_PATH environment variable.
56 --list-options
58 List available command options.
59
61 The lttng regenerate metadata command can only be used on kernel and
62 user space tracing sessions (using per-user buffering), in non-live
63 mode.
64 See lttng-enable-channel(1) for more information about buffering
66 schemes and lttng-create(1) for more information about the different
67 tracing session modes.
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70 LTTNG_ABORT_ON_ERROR
71 Set to 1 to abort the process after the first error is encountered.
72 LTTNG_HOME
74 Overrides the $HOME environment variable. Useful when the user
75 running the commands has a non-writable home directory.
76 LTTNG_MAN_BIN_PATH
78 Absolute path to the man pager to use for viewing help information
79 about LTTng commands (using lttng-help(1) or lttng COMMAND --help).
80 LTTNG_SESSION_CONFIG_XSD_PATH
82 Path in which the session.xsd session configuration XML schema may
83 be found.
84 LTTNG_SESSIOND_PATH
86 Full session daemon binary path.
87 The --sessiond-path option has precedence over this environment
89 variable.
90 Note that the lttng-create(1) command can spawn an LTTng session daemon
92 automatically if none is running. See lttng-sessiond(8) for the
93 environment variables influencing the execution of the session daemon.
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96 $LTTNG_HOME/.lttngrc
97 User LTTng runtime configuration.
98 This is where the per-user current tracing session is stored
100 between executions of lttng(1). The current tracing session can be
101 set with lttng-set-session(1). See lttng-create(1) for more
102 information about tracing sessions.
103 $LTTNG_HOME/lttng-traces
105 Default output directory of LTTng traces. This can be overridden
106 with the --output option of the lttng-create(1) command.
107 $LTTNG_HOME/.lttng
109 User LTTng runtime and configuration directory.
110 $LTTNG_HOME/.lttng/sessions
112 Default location of saved user tracing sessions (see lttng-save(1)
113 and lttng-load(1)).
114 /usr/local/etc/lttng/sessions
116 System-wide location of saved tracing sessions (see lttng-save(1)
117 and lttng-load(1)).
118 Note
120 $LTTNG_HOME defaults to $HOME when not explicitly set.
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123 0
124 Success
125 1
127 Command error
128 2
130 Undefined command
131 3
133 Fatal error
134 4
136 Command warning (something went wrong during the command)
137
139 If you encounter any issue or usability problem, please report it on
140 the LTTng bug tracker <https://bugs.lttng.org/projects/lttng-tools>.
141
143 · LTTng project website <http://lttng.org>
144 · LTTng documentation <http://lttng.org/docs>
146 · Git repositories <http://git.lttng.org>
148 · GitHub organization <http://github.com/lttng>
150 · Continuous integration <http://ci.lttng.org/>
152 · Mailing list <http://lists.lttng.org> for support and development:
154 lttng-dev@lists.lttng.org
155 · IRC channel <irc://irc.oftc.net/lttng>: #lttng on irc.oftc.net
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159 This program is part of the LTTng-tools project.
160 LTTng-tools is distributed under the GNU General Public License version
162 2 <http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html>. See the
163 LICENSE <https://github.com/lttng/lttng-tools/blob/master/LICENSE> file
164 for details.
165
167 Special thanks to Michel Dagenais and the DORSAL laboratory
168 <http://www.dorsal.polymtl.ca/> at École Polytechnique de Montréal for
169 the LTTng journey.
170 Also thanks to the Ericsson teams working on tracing which helped us
172 greatly with detailed bug reports and unusual test cases.
173
175 LTTng-tools was originally written by Mathieu Desnoyers, Julien
176 Desfossez, and David Goulet. More people have since contributed to it.
177 LTTng-tools is currently maintained by Jérémie Galarneau
179 <mailto:jeremie.galarneau@efficios.com>.
180
182 lttng(1)
183LTTng 2.10.7 05/24/2019 LTTNG-REGENERATE(1)