[lttng-dev] Tracepoints firing without being enabled in LTTng

Francis Deslauriers francis.deslauriers at efficios.com
Fri Feb 15 11:55:25 EST 2019

Adding back lttng-dev mailing list.

So you don't even run a lttng-enable-event command?
That's odd.

Can you send us the output of the following commands:
Is it possible that there are other lttng-sessiond daemons running on
the machine?
> ps aux | grep "lttng-sessiond"
Verify if there are other active tracing sessions:
> lttng list
Check the details of the current session:
> lttng status

Thank you,

Le ven. 15 févr. 2019, à 11 h 29, Mosleh Uddin <mosleh1235 at gmail.com> a écrit :
> Hi Francis,
> Thank you for the quick response.
> Just to clear things up, my application is running when I run that command.
> The commands I am running are:
> > lttng-sessiond -d
> > lttng create my-sess --live
> After this command I start my application. If I then do the command:
> > lttng view
> I will see the tracepoints in the application in the terminal even though I have not done: lttng start.
> I thought it was strange that I cannot find my application in the: lttng list command under any domain.
> Also the reason I start my application after creating a session is because the system automatically starts the application using systemd,
> in order to get tracing data at all I have to manually stop the application and start it again after creating a session.
> Thanks again for any help,
> Mosleh
> On Fri, Feb 15, 2019 at 10:32 AM Francis Deslauriers <francis.deslauriers at efficios.com> wrote:
>> Hi Mosleh,
>> It's expected to not see any event when running lttng list -u if no
>> lttng-ust instrumented applications are running.
>> What are the exact lttng commands you are running to see those
>> unexpected events?
>> Thank you,
>> Francis
>> Le ven. 15 févr. 2019, à 10 h 08, Mosleh Uddin <mosleh1235 at gmail.com> a écrit :
>> >
>> > Hello,
>> >
>> > I am having a strange issue with my current application. For some context, I have integrated LTTng into a Yocto build and put custom trace points in my embedded system application. Once I load the built image onto my system and start a session daemon, I try to list all available userspace events (using lttng list -u), but no events show up.
>> >
>> > The strange occurrence is when I create a session (lltng create my-sess) and not start tracing the trace events will display on the screen regardless (when starting session in live mode with lttng view). I was wondering if anyone has any insight on this issue I am having.
>> >
>> > Thanks for any assistance,
>> > Mosleh
>> > _______________________________________________
>> > lttng-dev mailing list
>> > lttng-dev at lists.lttng.org
>> > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
>> --
>> Francis Deslauriers
>> Computer Engineer
>> EfficiOS inc.

Francis Deslauriers
Computer Engineer
EfficiOS inc.

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