When it comes to maintenance outage, flume needs to be shutdown and offline
for a while. We want to make sure flume's WAL is completed before we shut
down the process. Is there anyway or any metrics exposed can indicate WAL
is fully processed so that it's safe to bring it down gracefully?
Of coz, the assumption here is that, the source of flume is not writing any
new data, flume only has a certain size backlog needs to be cleaned up.
All the best,