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Naveen Gangam commented on HIVE-23846: -------------------------------------- I have +1'ed the fix on PR. > Avoid unnecessary serialization and deserialization of bitvectors > ----------------------------------------------------------------- > > Key: HIVE-23846 > URL: https://issues.apache.org/jira/browse/HIVE-23846 > Project: Hive > Issue Type: Bug > Components: Standalone Metastore > Reporter: Yu-Wen Lai > Assignee: Yu-Wen Lai > Priority: Major > Labels: pull-request-available > Time Spent: 0.5h > Remaining Estimate: 0h > > In the method *getNdvEstimator* of <datatype>*ColumnStatsDataInspector*, it > will call isSetBitVectors(), in which it serializes the bitvectors again when > we already have deserialized bitvectors _ndvEstimator_. For example, we can > see this pattern from > [LongColumnStatsDataInspector|[https://github.com/apache/hive/blob/master/standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/columnstats/cache/LongColumnStatsDataInspector.java#L106]]. > This method could check if the _ndvEstimator_ is set first so that it won't > need to serialize and deserialize back. -- This message was sent by Atlassian Jira (v8.3.4#803005)