...
Extract the prefix “system.log.level”, get all the classes and levels. Then pass them to LogAppenderInitializer to change the log level for their loggers. For a flow, preferences with key format "flowlet.[flowletname].system.log.level.[class]" can be passed to change the log level of a specific flowlet. The idea is like how scoping works for system.resources.memory, we extract the scope of flowlet.name, and set the log level in FlowTwillRunnable.
Step 3: Remove some settings in logback-container.xml
...