Peng Zhang created YARN-3054: -------------------------------- Summary: Preempt policy in FairScheduler may cause mapreduce job never finish Key: YARN-3054 URL: https://issues.apache.org/jira/browse/YARN-3054 Project: Hadoop YARN Issue Type: Bug Components: fairscheduler Affects Versions: 2.6.0 Reporter: Peng Zhang
Preemption policy is related with schedule policy now. Using comparator of schedule policy to find preemption candidate cannot guarantee a subset of containers never be preempted. And this may cause tasks to be preempted periodically before they finish. So job cannot make any progress. I think preemption in YARN should got below assurance: 1. Mapreduce jobs can get additional resources when others are idle; 2. Mapreduce jobs for one user in one queue can still progress with its min share when others preempt resources back. Maybe always preempt the latest app and container can get this? -- This message was sent by Atlassian JIRA (v6.3.4#6332)