Impala Public Jenkins has submitted this change and it was merged. ( 
http://gerrit.cloudera.org:8080/11854 )

Change subject: IMPALA-7791: Compute AggregationNode's estimated rows using # 
instances
......................................................................

IMPALA-7791: Compute AggregationNode's estimated rows using # instances

Previously, the AggregationNode calculated the estimated number
of rows based on input cardinality without accounting for the
division of input data across multiple fragment instances. This
bloated up the memory estimates for the node. After this change,
the AggregationNode accounts for the number of fragment instances
while estimating the number of rows per instance. A skew factor of
1.5 was added to account for data skew among multiple fragment
instances. This number was derived using empirical analysis of
real-world and benchmark (tpch, tpcds) queries.

Testing:
Tested queries with changed estimates to avoid cases of
significant underestimation of memory.
Ran front-end and end-to-end tests affected by this change.

Change-Id: I2cb9746fafa3e5952e28caa952837e285bcc22ac
Reviewed-on: http://gerrit.cloudera.org:8080/11854
Reviewed-by: Impala Public Jenkins <[email protected]>
Tested-by: Impala Public Jenkins <[email protected]>
---
M fe/src/main/java/org/apache/impala/planner/AggregationNode.java
M testdata/workloads/functional-planner/queries/PlannerTest/max-row-size.test
M 
testdata/workloads/functional-planner/queries/PlannerTest/resource-requirements.test
M 
testdata/workloads/functional-planner/queries/PlannerTest/spillable-buffer-sizing.test
M testdata/workloads/functional-planner/queries/PlannerTest/tpcds-all.test
M testdata/workloads/functional-planner/queries/PlannerTest/tpch-all.test
M testdata/workloads/functional-planner/queries/PlannerTest/tpch-nested.test
7 files changed, 97 insertions(+), 82 deletions(-)

Approvals:
  Impala Public Jenkins: Looks good to me, approved; Verified

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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: merged
Gerrit-Change-Id: I2cb9746fafa3e5952e28caa952837e285bcc22ac
Gerrit-Change-Number: 11854
Gerrit-PatchSet: 4
Gerrit-Owner: Pooja Nilangekar <[email protected]>
Gerrit-Reviewer: Bikramjeet Vig <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins <[email protected]>
Gerrit-Reviewer: Pooja Nilangekar <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>

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