[ovirt-devel] [vdsm] logging levels and noise in the log

[Sven Kieske]

Am 10.07.2014 12:09, schrieb Martin Sivak:
> Hi,
> 
> we discussed the right amount of logging with Nir and Francesco while reviewing my patches. Francesco was against one DEBUG log message that could potentially flood the logs. But the message in question was important for me and SLA, because it was logging the VDSM changes in response to MoM command.
> 
> Since DEBUG really is meant to be used for debug messages, I have one proposal:
> 
> 1) Change the default log level of vdsm.log to INFO
> 2) Log (only) DEBUG messages to a separate file vdsm-debug.log
> 3) Make the vdsm-debug.log rotate faster (every hour, keep only last couple of hours?) so it does not grow too much
> 
> This way the customer would be able to monitor INFO logs (much smaller) without all the noise and we would be able to collect the DEBUG part in case something happens.
> 
> What do you think?


From a user perspective I can just encourage you to do so!
Log spam and finding relevant log messages are one of the hugest
drawbacks when using ovirt.

Since now all replies regarding this topic ended like this:
"it is not recommended to lower the default log levels because you
might need this information to debug problems".

But I beg to differ:

If this is a production ready software (after all it is sold somewhere)
you really should not need a log level of "debug" in a productive
environment.

This flag should be for development and test setups, and major breakage
should be fixed there (either in the setup, or in the code) and when
shipped, everyone should be comfortable with a loglevel of info or
warning.

My conclusion was until now: the ovirt devs don't trust their own
implementations to be robust enough and thus require debug flags.

I wonder when all those lurking bugs get fixed that prevent
the log level to get changed to "info" or "warning".

I have the feeling that the devs always want a "debug"
log level, no matter how much the product has matured.

Please correct me where I'm wrong, or share some
insight why these log levels are used and when it will
be possible to lower log levels.

running ovirt, from a log perspective, is like being forced
to run "ssh" always with option "-vvvvvv".

It makes debugging sometimes really hard, because the log
is spammed with so many messages which endusers(admins)
do not even understand that you don't find what you're actually
looking for and you need to waste time to filter the logs to
output what you searched for.

I'm sorry for this long rant, but I really don't understand
the current reasoning for this mess, as a user.

-- 
Mit freundlichen Grüßen / Regards

Sven Kieske

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