Sunil G created YARN-1662: ----------------------------- Summary: Capacity Scheduler reservation issue cause Job Hang Key: YARN-1662 URL: https://issues.apache.org/jira/browse/YARN-1662 Project: Hadoop YARN Issue Type: Bug Components: resourcemanager Affects Versions: 2.2.0 Environment: Suse 11 SP1 + Linux Reporter: Sunil G
There are 2 node managers in my cluster. NM1 with 8GB NM2 with 8GB I am submitting a Job with below details: AM with 2GB Map needs 5GB Reducer needs 3GB slowstart is enabled with 0.5 10maps and 50reducers are assigned. 5maps are completed. Now few reducers got scheduled. Now NM1 has 2GB AM and 3Gb Reducer_1 [Used 5GB] NM2 has 3Gb Reducer_2 [Used 3GB] A Map has now reserved(5GB) in NM1 which has only 3Gb free. It hangs forever. Potential issue is, reservation is now blocked in NM1 for a Map which needs 5GB. But the Reducer_1 hangs by waiting for few map ouputs. Reducer side preemption also not happened as few headroom is still available. -- This message was sent by Atlassian JIRA (v6.1.5#6160)