Henry Robinson has posted comments on this change. Change subject: IMPALA-2494: Support for byte array-encoded decimals in Parquet scanner ......................................................................
Patch Set 1: (2 comments) http://gerrit.cloudera.org:8080/#/c/5115/1//COMMIT_MSG Commit Message: Line 21: * Tested computing SUM(col) for 1 billion distinct dictionary-encoded > Can also verify on plain encoding? Seems like that would be the extreme cas Can do - but where would that extra slowness really come from? I would have thought decoding 1 billion values would represent a large portion of the execution time of such a simple query, and if the proportion is really that small I'm inclined to worry even less about the perf differential. Line 23: * No performance difference measured by introduction of extra > Did you run this with num_scanner_threads=1 or even better mt_dop=1? No, but I can do. What do you expect to change? -- To view, visit http://gerrit.cloudera.org:8080/5115 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: If95171e65aa48f08b08b8e87f4555dc75e867977 Gerrit-PatchSet: 1 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Henry Robinson <he...@cloudera.com> Gerrit-Reviewer: Alex Behm <alex.b...@cloudera.com> Gerrit-Reviewer: Henry Robinson <he...@cloudera.com> Gerrit-HasComments: Yes
