[lttng-dev] LTTng on Docker

Jérémie Galarneau jeremie.galarneau at efficios.com
Wed Apr 12 17:34:51 UTC 2017


On 11 April 2017 at 16:49, Jeffrey Chen <cpthk at live.com> wrote:

> I just tried using smaller value of subbuf size, and it works fine. I have
> 16GB of memory in my host, so I should have more than enough memory. The
> same size works fine in my host machine. My Docker container does not have
> any resource constraint. Do you know what could be the reason of the
> failure?
>
> Thanks.
>
>
My guess is some limitation or bug where the subbuffer size and tracefile
size can't be the same. I'll have to look into it.

Jérémie


>
> ------------------------------
> *From:* jeremie.galarneau at gmail.com <jeremie.galarneau at gmail.com> on
> behalf of Jérémie Galarneau <jeremie.galarneau at efficios.com>
> *Sent:* Monday, April 10, 2017 12:26 PM
>
> *To:* Jeffrey Chen
> *Cc:* lttng-dev at lists.lttng.org
> *Subject:* Re: [lttng-dev] LTTng on Docker
>
>
>
> On 10 April 2017 at 14:06, Jeffrey Chen <cpthk at live.com> wrote:
>
>> I have attached the logs from the lttng daemon. I could see errors like
>> below.
>>
>>
>> Error: Error creating UST channel "channel0" on the consumer daemon
>>
>>
>> My commands to create a session are:
>>
>> lttng create test
>> lttng enable-channel --session test --userspace --tracefile-size 8388608
>> --subbuf-size 8388608 channel0
>> lttng enable-event --channel channel0 --userspace "service:*"
>> lttng add-context -u -t vtid
>> lttng add-context -u -t vpid
>> lttng start
>>
>
> Thanks for the info. Can you try to create the channel with the default
> values and see if it works?
>
> $ lttng enable-channel --session test --userspace channel0
>
> Also, can you re-capture the session daemon logs launching it with the
> "-vvv --verbose-consumer" option since the problem appears to occur on the
> consumer's end.
>
> Thanks,
> Jérémie
>
>
>> Installed:
>> apt-get -y install lttng-tools lttng-modules-dkms liblttng-ust0
>> liblttng-ust-dev
>>
>> Thanks.
>>
>> ------------------------------
>> *From:* jeremie.galarneau at gmail.com <jeremie.galarneau at gmail.com> on
>> behalf of Jérémie Galarneau <jeremie.galarneau at efficios.com>
>> *Sent:* Sunday, April 9, 2017 2:06 PM
>> *To:* Jeffrey Chen
>> *Cc:* lttng-dev at lists.lttng.org
>> *Subject:* Re: [lttng-dev] LTTng on Docker
>>
>> On 7 April 2017 at 18:35, Jeffrey Chen <cpthk at live.com> wrote:
>> > Hi:
>> >
>> >
>> > I am trying to have LTTng UST tracing inside a docker container. I
>> wasn't
>> > able to get the UST tracing working. LTTng would not write any UST trace
>> > files in the directory, even though it printed it would. Has it been
>> tested
>> > before? Is there any known problem?
>>
>> Tracing inside a container (not Docker), where the LTTng daemons and
>> the applications are running in the same container, is known to work
>> as this is how most of the LTTng CI works.
>>
>> As far as Docker is concerned, I tested it a number of times and it
>> worked. Can you provide the versions of LTTng and Docker you're using
>> and the session daemon's logs (launching it with the -vvv option)?
>>
>> Thanks,
>> Jérémie
>>
>> >
>> >
>> > $ lttng enable-channel --session test --userspace channel0
>> >
>> > Error: Channel channel0: UST create channel failed (session
>> ServiceFabric_0)
>> > Error: Command error
>> >
>> >
>> > Thanks.
>> >
>> >
>> >
>> > _______________________________________________
>> > lttng-dev mailing list
>> > lttng-dev at lists.lttng.org
>> > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
>> lttng-dev Info Page
>> <https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev>
>> lists.lttng.org
>> To see the collection of prior postings to the list, visit the lttng-dev
>> Archives. Using lttng-dev: To post a message to all the list members, send
>> ...
>>
>> >
>>
>>
>>
>> --
>> Jérémie Galarneau
>> EfficiOS Inc.
>> http://www.efficios.com
>> EfficiOS <http://www.efficios.com/>
>> www.efficios.com
>> At EfficiOS, our main goal is diminishing the amount of time our clients
>> spend identifying faults. We also enable our clients' applications to scale
>> on massive multi ...
>>
>>
>
>
> --
> Jérémie Galarneau
> EfficiOS Inc.
> http://www.efficios.com
>



-- 
Jérémie Galarneau
EfficiOS Inc.
http://www.efficios.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.lttng.org/pipermail/lttng-dev/attachments/20170412/5d7f69cb/attachment-0001.html>


More information about the lttng-dev mailing list