Riza Suminto has posted comments on this change. ( http://gerrit.cloudera.org:8080/19033 )
Change subject: IMPALA-11604 Planner changes for CPU usage ...................................................................... Patch Set 37: (3 comments) http://gerrit.cloudera.org:8080/#/c/19033/37/fe/src/main/java/org/apache/impala/analysis/Expr.java File fe/src/main/java/org/apache/impala/analysis/Expr.java: http://gerrit.cloudera.org:8080/#/c/19033/37/fe/src/main/java/org/apache/impala/analysis/Expr.java@473 PS37, Line 473: public float evalCost() { return evalCost_; } This is unused. However, this point me to existing evalCost_ added in IMPALA-2805. We should experiment using that evalCost_ weighting vs equal cost of 1 per expression. http://gerrit.cloudera.org:8080/#/c/19033/37/fe/src/main/java/org/apache/impala/planner/PlanFragment.java File fe/src/main/java/org/apache/impala/planner/PlanFragment.java: http://gerrit.cloudera.org:8080/#/c/19033/37/fe/src/main/java/org/apache/impala/planner/PlanFragment.java@1025 PS37, Line 1025: childCostChange = adjustNonSharedJoinBuildChildCount(); I'm having a second thought on this join-build recomputation on non-shared join build (PARTITIONED). Since it is PARTITIONED, changing instance count of the join fragment will not change the output cardinality of join-build fragment. Hence, there will be no change in total processing cost of the exchange node, and recomputation is not necessary. http://gerrit.cloudera.org:8080/#/c/19033/37/fe/src/main/java/org/apache/impala/planner/ProcessingCost.java File fe/src/main/java/org/apache/impala/planner/ProcessingCost.java: http://gerrit.cloudera.org:8080/#/c/19033/37/fe/src/main/java/org/apache/impala/planner/ProcessingCost.java@40 PS37, Line 40: public final static long MIN_COST_PER_THREAD = 1000000L; This should be a backend flag instead of constant so that tuning is possible. -- To view, visit http://gerrit.cloudera.org:8080/19033 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: If32dc770dfffcdd0be2b5555a789a7720952c68a Gerrit-Change-Number: 19033 Gerrit-PatchSet: 37 Gerrit-Owner: Qifan Chen <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Kurt Deschler <[email protected]> Gerrit-Reviewer: Qifan Chen <[email protected]> Gerrit-Reviewer: Riza Suminto <[email protected]> Gerrit-Reviewer: Wenzhe Zhou <[email protected]> Gerrit-Comment-Date: Mon, 30 Jan 2023 20:25:12 +0000 Gerrit-HasComments: Yes
