doc/man/lttng-regenerate.1.txt

   1 lttng-regenerate(1)
   2 =================
   3
   4
   5 NAME
   6 ----
   7 lttng-regenerate - Manage an LTTng tracing session's data regeneration
   8
   9
  10 SYNOPSIS
  11 --------
  12 Regenerate the metadata of a session:
  13
  14 [verse]
  15 *lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *regenerate metadata* [option:--session='SESSION']
  16
  17 Regenerate the state dump of a session:
  18
  19 [verse]
  20 *lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *regenerate statedump* [option:--session='SESSION']
  21
  22 DESCRIPTION
  23 -----------
  24 The `lttng regenerate` command regenerates specific data of a tracing session.
  25
  26 As of this version, the `metadata` and `statedump` actions are
  27 available.
  28
  29
  30 Regenerating a tracing session's metadata
  31 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  32 The `lttng regenerate metadata` action can be used to resample the offset
  33 between the system's monotonic clock and the wall-clock time.
  34
  35 This action is meant to be used to resample the wall-clock time following a
  36 major link:https://en.wikipedia.org/wiki/Network_Time_Protocol[NTP] correction.
  37 As such, a system booting with an incorrect wall time can be traced before its
  38 wall time is NTP-corrected. Regenerating the tracing session's metadata ensures
  39 that trace viewers can accurately determine the events time relative to Unix
  40 Epoch.
  41
  42 If you use man:lttng-rotate(1) or man:lttng-enable-rotation(1) to make
  43 tracing session rotations, this action regenerates the current and
  44 next trace chunks's metadata files.
  45
  46
  47 Regenerating a tracing session's state dump
  48 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  49 The `lttng regenerate statedump` action can be used to collect up-to-date state
  50 dump information during the tracing session. This is particularly useful in
  51 snapshot (see man:lttng-snapshot(1)) or trace file rotation (see
  52 man:lttng-enable-channel(1)) modes where the state dump information may be
  53 lost.
  54
  55
  56 include::common-cmd-options-head.txt[]
  57
  58
  59 option:-s 'SESSION', option:--session='SESSION'::
  60     Regenerate the data of the tracing session named 'SESSION'
  61     instead of the current tracing session.
  62
  63
  64 include::common-cmd-help-options.txt[]
  65
  66
  67 LIMITATIONS
  68 -----------
  69 The `lttng regenerate metadata` command can only be used on kernel and
  70 user space tracing sessions (using per-user buffering), in non-live
  71 mode.
  72
  73 See man:lttng-enable-channel(1) for more information about
  74 buffering schemes and man:lttng-create(1) for more information
  75 about the different tracing session modes.
  76
  77
  78 include::common-cmd-footer.txt[]
  79
  80
  81 SEE ALSO
  82 --------
  83 man:lttng(1)