[ https://issues.apache.org/jira/browse/HDFS-5446?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kihwal Lee resolved HDFS-5446. ------------------------------ Resolution: Won't Fix > Consider supporting a mechanism to allow datanodes to drain outstanding work > during rolling upgrade > --------------------------------------------------------------------------------------------------- > > Key: HDFS-5446 > URL: https://issues.apache.org/jira/browse/HDFS-5446 > Project: Hadoop HDFS > Issue Type: Sub-task > Components: datanode > Affects Versions: 2.2.0 > Reporter: Nathan Roberts > > Rebuilding write pipelines is expensive and this can happen many times during > a rolling restart of datanodes (i.e. during a rolling upgrade). It seems like > it might help if datanodes could be told to drain current work while > rejecting new requests - possibly with a new response indicating the node is > temporarily unavailable (it's not broken, it's just going through a > maintenance phase where it shouldn't accept new work). > Waiting just a few seconds is normally enough to clear up a good percentage > of the open requests without error, thus reducing the overhead associated > with restarting lots of datanodes in rapid succession. > Obviously would need a timeout to make sure the datanode doesn't wait forever. -- This message was sent by Atlassian JIRA (v6.1.5#6160)