On 22 October 2015 at 19:35, Brian Robbins <[email protected]> wrote: > Hello, > > > > The Linux build of CoreCLR now supports tracing using LTTng-UST. One > artifact that we noticed when running on Ubuntu 14.04 in our CI is that apps > running on CoreCLR all have an LTTng warning written to stderr: > > > > libust[883/883]: Warning: HOME environment variable not set. Disabling > LTTng-UST per-user tracing. (in setup_local_apps() at lttng-ust-comm.c:305) > > > > I’ve investigated, and it is true that in the CI, there is no HOME > environment variable. However, what I’m more interested in is why this > message is written in the first place. Looking in at the latest LTTng-UST > code, it appears that this message should only be logged when debug logging > is enabled. From code inspection, it appears that debug logging can be > enabled at either compile time (#define LTTNG_UST_DEBUG) or at runtime via > an environment variable called LTTNG_UST_DEBUG. > > > > I have confirmed that the environment variable LTTNG_UST_DEBUG is not > present. I’ve also looked at the disassembly, and can confirm that the > ust_loglevel check is not actually performed (the if statement is optimized > away). This makes me think that the Ubuntu package was compiled with > LTTNG_UST_DEBUG defined. > > > > The package in question is old – LTTng-UST 2.4. I’m wondering if either > debug logging was always present in 2.4, or if the package was compiled with > LTTNG_UST_DEBUG. I would expect that most customers would want debug > logging off by default, since it affects the output of the program. > > > > Your help in figuring this out is greatly appreciated. > > > > Thank you. > > -Brian
Hi Brian, This warning used to appear regardless of the definition of LTTNG_UST_DEBUG. Bisecting shows that it has been fixed in commit 7bdd21a41092a59207958911666cbd458f93a319, which is part of version 2.7. Here it is: http://git.lttng.org/?p=lttng-ust.git;a=commit;h=7bdd21a41092a59207958911666cbd458f93a319 Simon _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
