LTTng » LTTng-UST

This is from Bernd, I think we should also take a moment to admire how awesome and meticulous his bug reports are.

Please find attached a tar file with the programs I used to create UST
traces where it seems that there are missing trace entries:

Please follow the following steps to build the 2 applications:

1) copy the tar file to a temp directory and change directory to it. I
will reference the temp directory with ${temp} below.
2) tar xvzf sequence.tar.gz
3) cd ${temp}/makefiles
4) Makefile.inc
4) Change variable BUILD_SUPPORT_DIR to use the absolute path of the
directory makefiles
5) cd ${temp}/sequence
6) make
> this will build 2 applications with name simple_client and
simple_server which are stored in ${temp}/sequence/server_bin and
${temp}/sequence/client_bin.

Use the following steps to create the traces:
1) Open 3 command shells (one for LTTng trace control, 1 for
simple_server application and 1 for the simple_client application)
2) For trace control:
2.1) lttng create mySession
2.2) lttng enable-event ust_seq* -u
2.3) lttng start
3) To start server (in server command shell):
3.1) cd ${temp}/sequence/server_bin
3.2) ./simple_server
4) To start a client:
4.1) cd ${temp}/sequence/client_bin
4.2) ./simple_client player1 20000

The client will initiate a connection to the server and will send 40008
signals to the server. The server will reply each message. After
stopping the trace and decoding the client trace or server trace, you
will see that there are traces missing (e.g for event type
ust_sequence:SEND).

Let me know if you have any questions or problems to run it.

BR
Bernd

How frequently can this be reproduced ? Can you try reproducing it on more systems ? I have tried to run your test program many times on my laptop (2-core, hyperthread) without success.

Thanks,

Mathieu

Cannot reproduce, no feedback for 6 months.