Reducers are always counted having "pending tasks" even if they can't be scheduled yet because not enough of their mappers have completed -----------------------------------------------------------------------------------------------------------------------------------------
Key: MAPREDUCE-2729 URL: https://issues.apache.org/jira/browse/MAPREDUCE-2729 Project: Hadoop Map/Reduce Issue Type: Improvement Environment: 0.20.1xx-Secondary Reporter: Sherry Chen Assignee: Sherry Chen In capacity scheduler, number of users in a queue needing slots are calculated based on whether users' jobs have any pending tasks. This works fine for map tasks. However, for reduce tasks, jobs do not need reduce slots until the minimum number of map tasks have been completed. Here, we add checking whether reduce is ready to schedule (i.e. if a job has completed enough map tasks) when we increment number of users in a queue needing reduce slots. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira