[GitHub] [hive] szlta opened a new pull request #1894: HIVE-24670

[GitBox <gi...@apache.org>]

szlta opened a new pull request #1894:
URL: https://github.com/apache/hive/pull/1894


   If delete delta caching is turned off, the plain record reader inside DeleteReaderValue allocates a batch with a schema that is equivalent to that of an insert delta.
   
   This is unnecessary as the struct part in a delete delta file is always empty. In cases where we have many delete delta files (e.g. due to compaction failures) and a wide table definition (e.g. 200+ cols) this puts a significant amount of memory pressure on the executor, while these empty structures will never be filled or otherwise utilized.
   
   I propose we specify an ACID schema with an empty struct part to this record reader to counter this.
   
   Options


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[GitHub] [hive] szlta merged pull request #1894: HIVE-24670

[GitBox <gi...@apache.org>]

szlta merged pull request #1894:
URL: https://github.com/apache/hive/pull/1894


   


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