[logback-user] appenders

[Eric Yung]

Hi,

I have migrated from log4j to slf4j and logback. I have one question for 
the appender setting. In log4j, you can set the threshold of an appender 
so that only a certain level of log messages will be logged by that 
appender. But in logback, I can only achieve this behavior by using a 
expression filter. I would like to know the performance figure about 
that filter. If the expression filter takes much longer than a dedicated 
log level filter, I would like to see a simple log level filter be 
included in logback.


Thanks,
Eric