Bug #724

babeltrace of flight recorder trace undergoes time warp?

Added by Daniel U. Thibault over 6 years ago. Updated 6 months ago.

Target version:
Start date:
Due date:
% Done:


Estimated time:


Assume a flight recorder trace is generated like this:

$ lttng create limkern
Session limkern created
Traces will be written in /home/daniel/lttng-traces/limkern-20140123-085831
$ lttng enable-channel channel0 -k --tracefile-size 262144 --tracefile-count 1
Kernel channel channel0 enabled for session limkern
$ lttng enable-event -k --all -c channel0
All kernel events are enabled in channel channel0
$ lttng start
(wait for a while)
$ lttng stop

Now when this is babeltraced:

$ babeltrace /home/daniel/lttng-traces/limkern-20140123-085831 -n all -f all -v -w /home/daniel/lttng-traces/limkern_nafav
[verbose] Verbose mode active
[warning] Tracer discarded 378942 events between [09:00:44.643712446] and [09:00:44.643710896] in trace UUID ce[...]22, at path: "/home/daniel/lttng-traces/limkern-20140123-085831/kernel", within stream id 0, at relative path: "channel_0_0_0". You should consider recording a new trace with larger buffers or with fewer events enabled.
[verbose] finished converting. Output written to:

Note how the lost events are said to lie in a nonsensical time span where the end (44.64371*0896*) is before the start (44.64371*2446*).

Using babeltrace 1.1.1-31-513413e.

Related to bug #589?

Related issues

Related to Babeltrace - Bug #589: Lost events time ranges may be offsetResolvedMathieu Desnoyers07/09/2013


Updated by Mathieu Desnoyers over 6 years ago

  • Target version changed from Babeltrace 1.1 to Babeltrace 1.2

Updated by Mathieu Desnoyers over 6 years ago

  • Assignee set to Mathieu Desnoyers

Updated by Mathieu Desnoyers over 6 years ago

Can you confirm that this commit fixes the issue ?

commit 2654fe9bab8f0eaeb17264ef7abadfd14e245b23
Author: Mathieu Desnoyers <>
Date:   Tue Feb 25 17:36:11 2014 -0500

    Fix: events discarded timing inaccuracy

    Introduce babeltrace_ctf_console_output too, to ensure we only print
    discarded events when a text output is used.

    Fixes #589

    Signed-off-by: Mathieu Desnoyers <>

Updated by Mathieu Desnoyers over 6 years ago

  • Status changed from New to Feedback

Updated by Jonathan Rajotte Julien 6 months ago

  • Status changed from Feedback to Resolved

State of babeltrace moved a lot since.

Closing this ticket. Reopen it if it stills apply to Babeltrace 2.

Also available in: Atom PDF