Hi, That looks like the TopN hash optimization didn't kick in, that must be a settings issue in the install.
| Reduce Output Operator | | key expressions: _col0 (type: string) | | sort order: + | | Statistics: Num rows: 1 Data size: 762813939712 Basic stats: PARTIAL Column stats: NONE | https://github.com/apache/hive/commit/265ae7b4f81ec7cf19c6f0b59a13a3e7dfb942e4#diff-ea752552821a2ae5f3a33c6db210ef0a I'd check if the configs for that are setup for you. Cheers, Gopal