Issues related to MediaWiki core's PSR debug logger, stats and timing services, and their configuration.
This includes:
- PSR-3 logging: The MediaWiki\Logger namespace of classes (such as Spi and Monolog integration), and their utility functions such as wfDebugLog(), and configuration such as $wgDebugLogFile and $wgDebugLogGroups.
- The debug toolbar.
- The StatsdDataFactory service and its wiring.
- The Timing class as used via RequestContext::getTiming.
For the debug profiler, refer to MediaWiki-Core-Profiler.
For the Metrics library (replacing StatsdDataFactory), refer to MediaWiki-libs-Stats.
For the shell.php and eval.php debugging tools, use the Shell & Eval column of MediaWiki-Maintenance-system.
For WMF's production infrastructure, refer to Wikimedia-Logstash.
To report production errors, use Wikimedia-production-error.