Details
Description
YARN-3424 changed logging of memory stats from ContainersMonitorImpl to INFO to DEBUG.
We have found these log messages to be useful information in Out-of-Memory situations - they provide detail that helps show the memory profile of the container over time, which can be helpful in determining root cause.
Here's an example message from YARN-3424:
2015-03-27 09:32:48,905 INFO org.apache.hadoop.yarn.server.nodemanager.containermanager.monitor.ContainersMonitorImpl: Memory usage of ProcessTree 9215 for container-id container_1427462602546_0002_01_000008: 189.8 MB of 1 GB physical memory used; 2.6 GB of 2.1 GB virtual memory used
Propose to change this to use a separate logger for this message, so that we can enable debug logging for this without enabling all of the other debug logging for ContainersMonitorImpl.