Reduce log clutter

[blaz-a]

Reduce log clutter by setting console_logging_verbosity_level to "errors only" (by setting console_logging_verbosity_level= 1) or "errors & warnings" (= 2) in proxysql.cnf; default is "errors, warnings & info" (= 3)

[mirostauder]

Automated message: PR pending admin approval for build testing

[renecannao]

Hi @blaz-a .

Thank you for the PR.

In #4478 (comment) I commented why I am against filtering a specific log entry, but the argument can be generalized.

• info/warning messages are extremely useful
• removing info/warning messages could obscure important information and make it more difficult to diagnose issues, both in the present and in the future. It is important to maintain comprehensive logs for troubleshooting and auditing purposes

Please note that these are not debug messages: debug messages are not even present in Release builds.

We are aware that some part of ProxySQL codebase can generate excessive verbosity, and there are variables that control such verbosity like mysql-hostgroup_manager_verbose .
For everything else, the general rule is that if a log entry is generated, it is very likely it is extremely useful.

I think we can consider applying general filtering only if every call to proxy_info() , proxy_warning() and proxysql_error() increases an internal counter, and is optionally exported as Prometheus stats and on disk stats.
Yet, we need some way to make sure that these entries are not lost. For example, if general filtering is applied, internal counters are always updated on disk stats.
Actually, I think I am going to create an issue to later implement this.

[blaz-a]

Hello @renecannao !

I agree with your point on usefulness of log messages and should therefore be enabled/shown by default.

However there might be cases where they are not needed and knowledgeable user should be given an option to reduce output verbosity. Approaching this at specific log levels seems the most common way of achieving this. This has been requested before here, I merely implemented the change. My PR maintains status quo - nothing changes unless the user explicitly modifies the proxysql.cnf setting and knowingly reduces log verbosity.

On the subject of keeping track of errors: PR only suppresses text output - the rest of the code is kept intact so that Prometheus counters etc. get updated accordingly. This means the tell-tale signs that attention is required are still there, it's just that log output that potentially gets reduced.

[mirostauder]

Can one of the admins verify this patch?