[ https://issues.apache.org/jira/browse/HDFS-7442?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Harsh J updated HDFS-7442: -------------------------- Affects Version/s: 2.6.0 > Optimization for decommission-in-progress check > ----------------------------------------------- > > Key: HDFS-7442 > URL: https://issues.apache.org/jira/browse/HDFS-7442 > Project: Hadoop HDFS > Issue Type: Improvement > Components: namenode > Affects Versions: 2.6.0 > Reporter: Ming Ma > > 1. {{isReplicationInProgress }} currently rescan all blocks of a given node > each time the method is called; it becomes less efficient as more of its > blocks become fully replicated. Each scan takes FS lock. > 2. As discussed in HDFS-7374, if the node becomes dead during decommission, > it is useful if the dead node can be marked as decommissioned after all its > blocks are fully replicated. Currently there is no way to check the blocks of > dead decomm-in-progress nodes, given the dead node is removed from blockmap. > There are mitigations for these limitations. Set > dfs.namenode.decommission.nodes.per.interval to small value for reduce the > duration of lock. HDFS-7409 uses global FS state to tell if a dead node's > blocks are fully replicated. > To address these scenarios, it will be useful to track the > decommon-in-progress blocks separately. -- This message was sent by Atlassian JIRA (v6.3.4#6332)