AFAIK, the asynch appender will only do the logging in a different thread, so the logging thread can return immediately, for those appender that might do "expensive" logging, but it won't apply this filter logic you need.
Yeah, that sounds quite reasonable. But I've seen a few mentions of people using it to do what I want somehow. In fact, there's a feature request here:
Is that just pure insanity? haha
Anyway, we'll keep playing with the filter. I'm just real surprised that no one's already done this.
Thanks for the sanity check. It's nice to have someone with more experience stop me from wasting a bunch of time. ;-)