impala-reviews mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Tim Armstrong (Code Review)" <ger...@cloudera.org>
Subject [Impala-ASF-CR] IMPALA-5612: join inversion should factor in parallelism
Date Mon, 21 Aug 2017 23:33:13 GMT
Tim Armstrong has posted comments on this change.

Change subject: IMPALA-5612: join inversion should factor in parallelism
......................................................................


Patch Set 5:

(7 comments)

http://gerrit.cloudera.org:8080/#/c/7351/5/fe/src/main/java/org/apache/impala/planner/Planner.java
File fe/src/main/java/org/apache/impala/planner/Planner.java:

Line 451:    * inversion.
> Returns false if any join input is missing relevant stats.
Done


Line 463:    * - the join strategy is PARTITIONED and rows are distributed evenly.
> I suggest you add a quick note why BROADCAST is not particularly relevant. 
Done. It was a bit tricky to explain crisply.


Line 473:    * The estimated cost of a hash join before and after inversion, measured in an
> estimated per-host cost
Done


Line 482:    * We choose b = 10 and C = 5 empirically because it seems to give reasonable
> You had this great spreadsheet over a wide range of inputs. Do you mind dum
I cleaned up the spreadsheet a bit and put it here:
https://docs.google.com/spreadsheets/d/1FA8phJRf9bLMS8yPhfQL7_peHiITW9XHSeltoRobhk4/edit?usp=sharing


Line 491:   private boolean isInvertedJoinCheaper(boolean isLocalPlan, JoinNode joinNode)
{
> nit: flip args to make them consistent with invertJoins()
Done


Line 509:     final long CONSTANT_COST_PER_ROW = 5;
> CONSTANT_COST_PER_BYTE?
Done


Line 518:       LOG.trace("lhsCard " + lhsCard + " lhsBytes " + lhsBytes +
> Also log the tblRefIds_ and/or tupleIds_ or the join, otherwise it will be 
Done


-- 
To view, visit http://gerrit.cloudera.org:8080/7351
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-MessageType: comment
Gerrit-Change-Id: Icacea4565ce25ef15aaab014684c9440dd501d4e
Gerrit-PatchSet: 5
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Tim Armstrong <tarmstrong@cloudera.com>
Gerrit-Reviewer: Alex Behm <alex.behm@cloudera.com>
Gerrit-Reviewer: Bharath Vissapragada <bharathv@cloudera.com>
Gerrit-Reviewer: Mostafa Mokhtar <mmokhtar@cloudera.com>
Gerrit-Reviewer: Tim Armstrong <tarmstrong@cloudera.com>
Gerrit-HasComments: Yes

Mime
View raw message