Description
When using realxLocality=true, it would be nice to have metrics to see how well the RM is fulfilling the requests. This helps to tune the relaxLocality params and compare the behavior.
The proposal is to have 3 metrics exposed via JMX
-node matching %
-rack matching %
-off_switch matching %
Each one represents the matching that occurred compared to the total matched asked.
The metrics would have to take into account the type of request (e.g node, ANY, etc)