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Sergey Shelukhin commented on HIVE-20853: ----------------------------------------- To fetch something, you first need to write something... currently that always happens in the same DAG I think. So in order to fetch smth from a node current DAG has to have written something there before or after restart. Before should be solved by this patch as far as I can tell, and after is solved because the task that wrote stuff already added credentials. [~gopalv] correct me if I'm wrong about shuffle and fetch :) > Expose ShuffleHandler.registerDag in the llap daemon API > -------------------------------------------------------- > > Key: HIVE-20853 > URL: https://issues.apache.org/jira/browse/HIVE-20853 > Project: Hive > Issue Type: Improvement > Components: llap > Affects Versions: 3.1.0 > Reporter: Jaume M > Assignee: Jaume M > Priority: Critical > Attachments: HIVE-20853.1.patch, HIVE-20853.2.patch, > HIVE-20853.3.patch, HIVE-20853.4.patch > > > Currently DAGs are only registered when a submitWork is called for that DAG. > At this point the crendentials are added to the ShuffleHandler and it can > start serving. > However Tez might (and will) schedule tasks to fetch from the ShuffleHandler > before anything of this happens and all this tasks will fail which may > results in the query failing. > This happens in the scenario in which a LlapDaemon just comes up and tez > fetchers try to open a connection before a DAG has been registered. > Adding this API will allow to register the DAG against the Daemon when the AM > notices that a new Daemon is up. -- This message was sent by Atlassian JIRA (v7.6.3#76005)