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Gopal V edited comment on HIVE-20279 at 8/7/18 8:23 PM: -------------------------------------------------------- [~ashutoshc]: this patch is probably too fragile - I chased this bug down to DruidQueryRecordReader not implementing ::getPos(). https://github.com/apache/hive/blob/master/druid-handler/src/java/org/apache/hadoop/hive/druid/serde/DruidQueryRecordReader.java#L145 was (Author: gopalv): [~ashutoshc]: this patch is probably too fragile - I chased this bug down to DruidQueryRecordReader not implementing ::getPos(). > HiveContextAwareRecordReader slows down Druid Scan queries. > ------------------------------------------------------------ > > Key: HIVE-20279 > URL: https://issues.apache.org/jira/browse/HIVE-20279 > Project: Hive > Issue Type: Improvement > Reporter: Nishant Bangarwa > Assignee: Nishant Bangarwa > Priority: Major > Attachments: HIVE-20279.1.patch, HIVE-20279.patch, scan2.svg > > > HiveContextAwareRecordReader add lots of overhead for Druid Scan Queries. > See attached flame graph. > Looks like the operations for checking for existence of footer/header buffer > takes most of time For druid and other storage handlers that do not have > footer buffer we should skip the logic for checking the existence for storage > handlers atleast. -- This message was sent by Atlassian JIRA (v7.6.3#76005)