Riza Suminto has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/20498 )

Change subject: IMPALA-12018: Consider runtime filter for cardinality reduction
......................................................................


Patch Set 16:

(2 comments)

http://gerrit.cloudera.org:8080/#/c/20498/16//COMMIT_MSG
Commit Message:

http://gerrit.cloudera.org:8080/#/c/20498/16//COMMIT_MSG@12
PS16, Line 12: that
nit: than


http://gerrit.cloudera.org:8080/#/c/20498/16/fe/src/main/java/org/apache/impala/planner/ExchangeNode.java
File fe/src/main/java/org/apache/impala/planner/ExchangeNode.java:

http://gerrit.cloudera.org:8080/#/c/20498/16/fe/src/main/java/org/apache/impala/planner/ExchangeNode.java@306
PS16, Line 306: getCardinality()
I found a potential issue in resource estimation of EXCHANGE node.
If getCardinality() is abnormally low here (and in 
estimateDeferredRPCQueueSize()) after runtime filter reduction, 
estimatedTotalQueueByteSize may be severely underestimate.

SCAN and JOIN node is not impacted.
SCAN node estimate is based on scan range count before runtime filter reduction.
JOIN node estimate use cardinality, but of the build side.
This patch operate on the probe pipeline, so no impact there for JOIN memory 
estimate.

I think this patch should be modified to focus on using reduced cardinality for 
ProcessingCost only. Resource estimation should keep using original cardinality 
before runtime filter so that memory estimate stay conservative.



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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I033789c9b63a8188484e3afde8e646563918b3e1
Gerrit-Change-Number: 20498
Gerrit-PatchSet: 16
Gerrit-Owner: Riza Suminto <[email protected]>
Gerrit-Reviewer: Abhishek Rawat <[email protected]>
Gerrit-Reviewer: Aman Sinha <[email protected]>
Gerrit-Reviewer: Csaba Ringhofer <[email protected]>
Gerrit-Reviewer: Daniel Becker <[email protected]>
Gerrit-Reviewer: David Rorke <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Riza Suminto <[email protected]>
Gerrit-Comment-Date: Thu, 14 Dec 2023 23:14:45 +0000
Gerrit-HasComments: Yes

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