Tim Armstrong has posted comments on this change. ( http://gerrit.cloudera.org:8080/8085 )
Change subject: IMPALA-5307: part 1: don't transfer disk I/O buffers out of parquet ...................................................................... Patch Set 10: Mostafa, we spoke offline about this but just wanted to confirm it looked ok to you. The summary is that the CPU cost of value materialisation for non-dict-encoded strings in uncompressed parquet scans regresses to roughly the same CPU cost as snappy-compressed parquet. I didn't see any regressions on TPC-H, only narrowly targeted benchmarks. -- To view, visit http://gerrit.cloudera.org:8080/8085 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I767c1e2dabde7d5bd7a4d5c1ec6d14801b8260d2 Gerrit-Change-Number: 8085 Gerrit-PatchSet: 10 Gerrit-Owner: Tim Armstrong <[email protected]> Gerrit-Reviewer: Alex Behm <[email protected]> Gerrit-Reviewer: Dan Hecht <[email protected]> Gerrit-Reviewer: Lars Volker <[email protected]> Gerrit-Reviewer: Mostafa Mokhtar <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-Comment-Date: Wed, 18 Oct 2017 19:12:22 +0000 Gerrit-HasComments: No
