Harsh J created YARN-1200: ----------------------------- Summary: Provide a central view for rack topologies Key: YARN-1200 URL: https://issues.apache.org/jira/browse/YARN-1200 Project: Hadoop YARN Issue Type: Improvement Components: resourcemanager Affects Versions: 2.1.0-beta Reporter: Harsh J
It appears that with YARN, any AM (such as the MRv2 AM) that tries to do rack-info-based work, will need to resolve racks locally rather than get rack info from YARN directly: https://github.com/apache/hadoop-common/blob/trunk/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/main/java/org/apache/hadoop/mapreduce/v2/app/rm/RMContainerAllocator.java#L1054 and its use of a simple implementation of https://github.com/apache/hadoop-common/blob/trunk/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/RackResolver.java This is a regression, as we've traditionally only had users maintain rack mappings and its associated script on a single master role node (JobTracker), not at every compute node. Task spawning hosts have never done/needed rack resolution of their own. It is silly to have to maintain rack configs and their changes on all nodes. We should have the RM host a stable interface service so that there's only a single view of the topology across the cluster, and document for AMs to use that instead. -- 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