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Vinayakumar B commented on HDFS-9044: ------------------------------------- +1, pending jenkins > Give Priority to FavouredNodes , before selecting nodes from FavouredNode's > Node Group > -------------------------------------------------------------------------------------- > > Key: HDFS-9044 > URL: https://issues.apache.org/jira/browse/HDFS-9044 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: J.Andreina > Assignee: J.Andreina > Attachments: HDFS-9044.1.patch, HDFS-9044.2.patch, HDFS-9044.3.patch, > HDFS-9044.4.patch, HDFS-9044.5.patch, HDFS-9044.6.patch > > > Passing Favored nodes intention is to place replica among the favored node > Current behavior in Node group is > If favored node is not available it goes to one among favored > nodegroup. > {noformat} > Say for example: > 1)I need 3 replicas and passed 5 favored nodes. > 2)Out of 5 favored nodes 3 favored nodes are not good. > 3)Then based on BlockPlacementPolicyWithNodeGroup out of 5 targets node > returned , 3 will be random node from 3 bad FavoredNode's nodegroup. > 4)Then there is a probability that all my 3 replicas are placed on > Random node from FavoredNodes's nodegroup , instead of giving priority to 2 > favored nodes returned as target. > {noformat} > *Instead of returning 5 targets on 3rd step above , we can return 2 good > favored nodes as target* > *And remaining 1 needed replica can be chosen from Random node of bad > FavoredNodes's nodegroup.* > This will make sure that the FavoredNodes are given priority. -- This message was sent by Atlassian JIRA (v6.3.4#6332)