[ https://issues.apache.org/jira/browse/MAPREDUCE-3951?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Sandy Ryza resolved MAPREDUCE-3951. ----------------------------------- Resolution: Not A Problem > Tasks are not evenly spread throughout cluster in MR2 > ----------------------------------------------------- > > Key: MAPREDUCE-3951 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-3951 > Project: Hadoop Map/Reduce > Issue Type: Improvement > Components: scheduler > Affects Versions: 0.23.0, 0.24.0 > Reporter: Todd Lipcon > > In MR1 (at least with the fair and fifo schedulers), if you submit a job that > needs fewer resources than the cluster can provide, the tasks are spread > relatively evenly across the node. For example, submitting a 100-map job to a > 50-node cluster, each with 10 slots, results in 2 tasks on each machine. In > MR2, however, the tasks would pile up on the first 10 nodes of the cluster, > leaving the other nodes unused. This is highly suboptimal for many use cases. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira