Adar Dembo has posted comments on this change. ( http://gerrit.cloudera.org:8080/15064 )
Change subject: schema: use dense_hash_map instead of std::unordered_map ...................................................................... Patch Set 3: (1 comment) http://gerrit.cloudera.org:8080/#/c/15064/1//COMMIT_MSG Commit Message: http://gerrit.cloudera.org:8080/#/c/15064/1//COMMIT_MSG@9 PS1, Line 9: In a time series benchmark I'm working on, the client spent 12% of its : CPU in Schema::FindColumn. In particular, most of the CPU went to the : bucket calculation in std::unordered_map, which required a 'divq' : instruction that can take hundreds of cycles. > if it's OK, I'll decline on this -- there are a bunch of microbenchmarks fl Sure. I wasn't referring to that choice so much as an approximation of the particular Kudu workload you're experimenting with that happens to spend so much time in FindColumn. -- To view, visit http://gerrit.cloudera.org:8080/15064 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: kudu Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I8e8f80229b2dcfad05e204a6f6e50ce7dc3f4c73 Gerrit-Change-Number: 15064 Gerrit-PatchSet: 3 Gerrit-Owner: Todd Lipcon <[email protected]> Gerrit-Reviewer: Adar Dembo <[email protected]> Gerrit-Reviewer: Alexey Serbin <[email protected]> Gerrit-Reviewer: Kudu Jenkins (120) Gerrit-Reviewer: Todd Lipcon <[email protected]> Gerrit-Comment-Date: Sat, 18 Jan 2020 00:11:52 +0000 Gerrit-HasComments: Yes
