Can't run LTTng analysis on traced data

[vecxim]

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I tried using LTTng analysis for tracing and started with the given samples from the manual:

I use ubuntu on a VM and installed all necessary packages. I used the given example to collect the trace data as described within the manual:

lttng-analyses-record

After I recorded some events I tried analysing them:

sudo lttng-cputop lttng-analysis-17045-20200818-174021

When executing this command I will get tons of warnings and an error at the end:

[warning] Unknown value 0 in enum.
[warning] Unknown value 0 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 1569 in enum.
[warning] Unknown value 1569 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
[warning] Unknown value 33 in enum.
Error: Cannot run analysis: 'pid'  

I also tried the same command on the sample trace provided in the manual and it works flawless.

Im really not sure what I am doing wrong here, I also used a clean VM and reinstalled all neccessary packages without success.

[weijk2533]

hello, I meet this problem today. After one day test, I finally find that when using Ubuntu, you can not follow the STEP 1, just start form step 2. Hope this will solve your problem too

In general, Just do not do the following three X sudo apt-get install -y software-properties-common X sudo apt-add-repository -y ppa:lttng/ppa X sudo apt-get update

do not !

[Trass3r]

That's cause the PPA will give you lttng 2.13+. If you add --debug to the analyze commands you get to the actual error, pid got removed from lttng_statedump_file_descriptor, though it's unclear in which version: https://lwn.net/Articles/816142/, https://lttng.org/docs/v2.13/#doc-whats-new

[kienanstewart]

Adding the following command to the manual tracing steps before running lttng start can work-around this issue:

lttng add-context --kernel --type=pid