| Re: [tracecompass-dev] How To View Live Traces |
I am running trace compass as user, but the trace is saved in /root/lttng-traces/localhost instead of what I would expect, /home/user/lttng-traces/localhost. Now after starting the trace and adding trace points, when I click import I get the error:
Error initializing live trace.
Cannot create linked resource. Local location '/root/lttng-traces/localhost/NEWustTest-20160322-170122/ust/uid/500/64-bit' does not exist.But I see the folder at that location...although it is owned by root...Just to clarify, the user is in the tracing group and has sudo permissions for lttng commands.On Tue, Mar 22, 2016 at 12:57 PM, Bernd Hufmann <bernd.hufmann@xxxxxxxxxxxx> wrote:Hi Michael
this error seems to indicate that no trace events have been created by the application and the metadata file hasn't been created when the live trace is imported by you pressing the import button. After starting the trace session could you please check the trace destination directory if the metadata file exists. The directory should look something like this:
${user-home}/lttng-traces/{node-name}/{session-name}${date-time}/ust/uid/45167/64-bit
Bernd
On 03/22/2016 10:49 AM, Michael Steppe wrote:
Same with a live UST trace
On Tue, Mar 22, 2016 at 10:19 AM, Michael Steppe <msteppe91@xxxxxxxxx> wrote:
So I have updated the lttng kernel modules to 2.6.4, the lttng ust packages to 2.6.1, and the lttng tools packages to 2.6.5. When attempting to import the live kernel trace I get the error I attached in the previous email: "Error, trace has no metadada"
Any suggestions? I am coming down to the wire on this project so any help would be great! :)
On Mon, Mar 21, 2016 at 9:16 AM, Michael Steppe <msteppe91@xxxxxxxxx> wrote:
Sorry, I forgot to include this earlier. Here is a screenshot of the new error I am seeing:
On Mon, Mar 21, 2016 at 9:15 AM, Michael Steppe <msteppe91@xxxxxxxxx> wrote:
-MichaelI plan on waiting for the new kernel modules that match my Gaia versions of the tools and ust packages to really test this, but if anything stands out to you guys as other things I may need to do to in order to get this working, help would be appreciated!I created a live session through the control view and enabled all ust events. The import button is now available to click after starting the trace! Woohoo! Unfortunately, regardless if I click the import button before or after the trace is started, I get an error saying "Error, trace has no metadata". I figured this may be because no userspace trace points have been created on the system. I added a trace point manually from the command line while the trace was running then clicked on the import button and still go the same error. If I click the import button again, I get the "null argument" error I had been getting before. Only the first time per session when clicking the import button do I see the "no metadata" error.Because the issue seemed to have to do with the "lttng create" command, I figured I could at least test userspace live trace viewing in Trace Compass with my old 2.4.4 kernel modules installed until my co-worker could get me the new kernel modules. Correct me if I am wrong but I should be able to do this if I am just enabling userspace event in the session...All,Here is a little update on my attempt to view live traces in a 2.6.32 kernel. I downloaded and built from source the userspace-rcu (0.9.1), lttng-tools (2.6.5), and lttng-ust (2.6.1) listed under the "Gaia" release on LTTng's website (http://lttng.org/download/). Meanwhile, my co-worker is attempting to build the kernel modules (2.6.4) that go along with the Gaia release.