The initial design called for the node manager to write YARN container events to take advantage of the distributed writes. RM acting as a sole writer of all YARN container events would have significant scalability problems.
Still, there are some types of events that are not captured by the NM. The current implementation has both: RM writing container events and NM writing container events.
We need to sort this out, and decide how we can write all needed container events in a scalable manner.