[jira] [Comment Edited] (ARROW-3051) [C++] Status performance optimization from Impala/Kudu
[ https://issues.apache.org/jira/browse/ARROW-3051?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16580379#comment-16580379 ] Dimitri Vorona edited comment on ARROW-3051 at 8/15/18 7:51 AM: In that case copy-elision won't work even with the change [http://cpp.sh/3x25h] . Even worse: while using const reference with temporary gives a correct behaviour, it disables RVO, since it isn't specified to work on references (see returnNoisy[2-4]). EDIT: OTOH, if we return a new Status::OK() in the end of the function, which is common, RVO won't work anyway, and we save ourselves a copy in the most common case (i.e. when status is ok). OK Status copy being virtually free, I doubt we could produce any numbers showing the difference, but I can't think of any reasonable example, were it could make things worse. was (Author: alendit): In that case copy-elision won't work even with the change [http://cpp.sh/3x25h] . Even worse: while using const reference with temporary gives a correct behaviour, it disables RVO, since it isn't specified to work on references (see returnNoisy[2-4]). EDIT: OTOH, if we return a new Status::OK() in the end of the function, which is common, RVO won't work anyway, and we save ourselves a copy in the most common case (i.e. when status is ok). OK Status copy being virtually free, I doubt we could produce any numbers, but I can't think of any reasonable example, were it could make things worse. > [C++] Status performance optimization from Impala/Kudu > -- > > Key: ARROW-3051 > URL: https://issues.apache.org/jira/browse/ARROW-3051 > Project: Apache Arrow > Issue Type: Improvement > Components: C++ >Reporter: Wes McKinney >Priority: Major > Fix For: 0.11.0 > > > Just saw this patch, worth investigating: > https://github.com/apache/impala/commit/ea615d1d8026dbe1cda3f5c2b048d210b2df435b -- This message was sent by Atlassian JIRA (v7.6.3#76005)
[jira] [Comment Edited] (ARROW-3051) [C++] Status performance optimization from Impala/Kudu
[ https://issues.apache.org/jira/browse/ARROW-3051?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16580379#comment-16580379 ] Dimitri Vorona edited comment on ARROW-3051 at 8/15/18 7:50 AM: In that case copy-elision won't work even with the change [http://cpp.sh/3x25h] . Even worse: while using const reference with temporary gives a correct behaviour, it disables RVO, since it isn't specified to work on references (see returnNoisy[2-4]). EDIT: OTOH, if we return a new Status::OK() in the end of the function, which is common, RVO won't work anyway, and we save ourselves a copy in the most common case (i.e. when status is ok). OK Status copy being virtually free, I doubt we could produce any numbers, but I can't think of any reasonable example, were it could make things worse. was (Author: alendit): In that case copy-elision won't work even with the change [http://cpp.sh/3x25h] . Even worse: while using const reference with temporary gives a correct behaviour, it disables RVO, since it isn't specified to work on references (see returnNoisy[2-4]). > [C++] Status performance optimization from Impala/Kudu > -- > > Key: ARROW-3051 > URL: https://issues.apache.org/jira/browse/ARROW-3051 > Project: Apache Arrow > Issue Type: Improvement > Components: C++ >Reporter: Wes McKinney >Priority: Major > Fix For: 0.11.0 > > > Just saw this patch, worth investigating: > https://github.com/apache/impala/commit/ea615d1d8026dbe1cda3f5c2b048d210b2df435b -- This message was sent by Atlassian JIRA (v7.6.3#76005)
[jira] [Comment Edited] (ARROW-3051) [C++] Status performance optimization from Impala/Kudu
[ https://issues.apache.org/jira/browse/ARROW-3051?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16580379#comment-16580379 ] Dimitri Vorona edited comment on ARROW-3051 at 8/14/18 8:21 PM: In that case copy-elision won't work even with the change [http://cpp.sh/3x25h] . Even worse: while using const reference with temporary gives a correct behaviour, it disables RVO, since it isn't specified to work on references (see returnNoisy[2-4]). was (Author: alendit): In that case copy-elision won't work either [http://cpp.sh/3x25h] . Even worse: while using const reference with temporary gives a correct behaviour, it disables RVO, since it isn't specified to work on references (see returnNoisy[2-4]). > [C++] Status performance optimization from Impala/Kudu > -- > > Key: ARROW-3051 > URL: https://issues.apache.org/jira/browse/ARROW-3051 > Project: Apache Arrow > Issue Type: Improvement > Components: C++ >Reporter: Wes McKinney >Priority: Major > Fix For: 0.11.0 > > > Just saw this patch, worth investigating: > https://github.com/apache/impala/commit/ea615d1d8026dbe1cda3f5c2b048d210b2df435b -- This message was sent by Atlassian JIRA (v7.6.3#76005)
