Csaba Ringhofer has posted comments on this change. ( http://gerrit.cloudera.org:8080/9576 )
Change subject: IMPALA-6638: Reduce file handle cache lock contention ...................................................................... Patch Set 1: (1 comment) This change can increase the number of parallel calls to the namenode by FileHandleCache, which was limited by the number of partitions before. I do not know if this can cause problems or not, but I would prefer to mention it as a possible side effect, or limit the number of parallel hdfsOpenFile calls somehow. http://gerrit.cloudera.org:8080/#/c/9576/1/be/src/runtime/io/handle-cache.inline.h File be/src/runtime/io/handle-cache.inline.h: http://gerrit.cloudera.org:8080/#/c/9576/1/be/src/runtime/io/handle-cache.inline.h@129 PS1, Line 129: pair<typename MapType::iterator, typename MapType::iterator> range = : p.cache.equal_range(*fname); : FileHandleEntry entry(new_fh, p.lru_list); : typename MapType::iterator new_it = p.cache.emplace_hint(range.second, : *fname, std::move(entry)); Does the hint logic make a difference anymore? I think that it would be better to replace emplace_hint() with emplace() and remove equal_range(). -- To view, visit http://gerrit.cloudera.org:8080/9576 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I4c695b21ca556e9c73c703c0c891e64939271c8d Gerrit-Change-Number: 9576 Gerrit-PatchSet: 1 Gerrit-Owner: Joe McDonnell <joemcdonn...@cloudera.com> Gerrit-Reviewer: Csaba Ringhofer <csringho...@cloudera.com> Gerrit-Comment-Date: Mon, 12 Mar 2018 16:11:11 +0000 Gerrit-HasComments: Yes
