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Chao commented on HIVE-8486: ---------------------------- OK, I debugged this query. In {{SetSparkReducerParallelism}}, in order to estimate, it needs to obtain statistics from the siblings of the current reduce sink, and adds up the total number of bytes. However, somehow the {{statistics}} field of all the siblings are null, and hence the number of bytes is 0 at end. As result, it will only use one reducer. I'm wondering if this is something we haven't implemented yet, or is it a bug? > TPC-DS Query 96 parallelism is not set correcly > ----------------------------------------------- > > Key: HIVE-8486 > URL: https://issues.apache.org/jira/browse/HIVE-8486 > Project: Hive > Issue Type: Sub-task > Components: Spark > Reporter: Brock Noland > Assignee: Chao > > When we run the query on a 20B we only have a parallelism factor of 1. -- This message was sent by Atlassian JIRA (v6.3.4#6332)