Thank you for the detailed answer.
I think I have sorted it all out.
My use case is an i3 session started with some session manager like gdm
or kdm (or any other *dm).
In that setup, the users have little access to the arguments passed to i3.
Let's assume the system uses an i3 build from git@master.
It should be sufficient to start i3 as "i3 --shmlog-size=25000000 -V -d
all" to get extended logs including the starting phase, and suitable for
bug reports.
If users are annoyed by the memory usage, they can add 'exec
--no-startup-id i3-msg shmlog no' to their config.
This way, I enable users to
1) access complete logs suitable for debug without needing root access
2) disable i3 logging if they do not want it
If it is not an up-to-date git build, they can still use the logs it for
their own debug purposes.
Do you think the idea of always starting i3 with the
"--shmlog-size=25000000 -V -d all" parameters makes sense ?
--
Regards,
Layus
On 27/10/15 15:22, Michael Stapelberg wrote:
On Tue, Oct 27, 2015 at 7:01 AM, Guillaume Maudoux (Layus)
<layus...@gmail.com> wrote:
Hello world!
I am trying to enable debugging in i3, and I am confused by the
number of different options to do this.
command line config option
-- -------------------- -----------------------------
1 i3 --shmlog-size=X shmlog on|off|toggle|<size>
Note that “shmlog on|off|toggle|<size>” refers to a command, not a
config directive.
2 i3 -V ?
Errors (ELOG in the code) are always printed to stdout.
Verbose log messages (LOG in the code) are printed to stdout if -V is
enabled. Intended for curious users.
Debug log messages (DLOG in the code) are printed if -d is enabled.
3 i3 -d all ?
4 ? debuglog on|off|toggle
3 and 4 are the same setting. The “all” argument to -d is obsolete,
but kept for backwards compatibility.
See also https://github.com/i3/i3/issues/1823 for a related discussion.
So my question are:
Which one is the recommended way ?
The recommended way is to use an automatically built version from
http://i3wm.org/docs/repositories.html (or i3-git if your package
manager knows how to build automatically build software from git)
because otherwise any of your findings will need to be confirmed again
on a more recent version.
These versions automatically enable debug logging to shared memory
(they check whether they were built from a git version that is not a
release version).
Does `shmlog on` imply `debuglog on` ?
No.
Does `-d all` imply `-V` ?
No.
What size do you recommend for the shmlog size ?
25MB (arbitrarily chosen, but proven to be enough for all issues we’ve
encountered so far).
May I assume that the config options cannot be used to debug
issues prior to loading the configuration file (nor issues while
loading the configuration file) ?
If you specify them as command-line parameters to i3, they will be
active before loading the configuration file.
Which of these options provide enough information for a bug report
? Is -V enough ?
Please use -V -d all, as per section 2 of
http://i3wm.org/docs/debugging.html
It seems that shm logging is better in the sense that it does not
increase a log file size, but not as nice as it locks some memory
space.
Correct.
What is the reason behind shm logging, instead of the usual
logging to file + logrotate ?
It’s easier for us to set aside a chunk of memory than to make sure
that every user of i3 knows about having to logrotate a file away.
Anecdotally, we’ve had a bunch of users whose hard drive (or RAM, in
case of /tmp being on tmpfs) filled up because of an ever-growing i3
logfile.
--
Best regards,
Michael
