[ https://issues.apache.org/jira/browse/HDFS-6268?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Andrew Wang updated HDFS-6268: ------------------------------ Status: Patch Available (was: Open) > Better sorting in NetworkTopology#pseudoSortByDistance when no local node is > found > ---------------------------------------------------------------------------------- > > Key: HDFS-6268 > URL: https://issues.apache.org/jira/browse/HDFS-6268 > Project: Hadoop HDFS > Issue Type: Improvement > Affects Versions: 2.4.0 > Reporter: Andrew Wang > Assignee: Andrew Wang > Priority: Minor > Attachments: hdfs-6268-1.patch > > > In NetworkTopology#pseudoSortByDistance, if no local node is found, it will > always place the first rack local node in the list in front. > This became an issue when a dataset was loaded from a single datanode. This > datanode ended up being the first replica for all the blocks in the dataset. > When running an Impala query, the non-local reads when reading past a block > boundary were all hitting this node, meaning massive load skew. -- This message was sent by Atlassian JIRA (v6.2#6252)