impala-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Skye Wanderman-Milne (Code Review)" <>
Subject [Impala-CR](cdh5-trunk) IMPALA-3311: fix string data coming out of aggs in subplans
Date Wed, 11 May 2016 00:44:34 GMT
Skye Wanderman-Milne has posted comments on this change.

Change subject: IMPALA-3311: fix string data coming out of aggs in subplans

Patch Set 1:

File be/src/exec/

Line 370:   for (int i = 0; i < aggregate_evaluators_.size(); ++i) {
> This is a pretty big block of code, I think it'd be more readable if it was
I moved the string copying code to its own function. Lemme know if you think I should factor
out more.

Line 374:     if (IsInSubplan()) {
> Makes sense. Is it worth adding a targeted perf query to check we don't reg
I'm having trouble writing a good query that really isolates this effect and isn't too complicated.
I have a query where the effect is noticeable, but the subplan still dominates the time (2s
vs 2.4s locally, but the non-subplan aggregation time doubles). I'll post what I have.

Line 380:       for (int i = first_row_idx; i < row_batch->num_rows(); ++i, ++row) {
> You could use the new RowBatch::Iterator. I think you're doing exactly what

To view, visit
To unsubscribe, visit

Gerrit-MessageType: comment
Gerrit-Change-Id: Iada891504c261ba54f4eb8c9d7e4e5223668d7b9
Gerrit-PatchSet: 1
Gerrit-Project: Impala
Gerrit-Branch: cdh5-trunk
Gerrit-Owner: Skye Wanderman-Milne <>
Gerrit-Reviewer: Dan Hecht <>
Gerrit-Reviewer: Skye Wanderman-Milne <>
Gerrit-Reviewer: Tim Armstrong <>
Gerrit-HasComments: Yes

View raw message