Joe McDonnell has uploaded this change for review. ( 
http://gerrit.cloudera.org:8080/23074


Change subject: IMPALA-13898: Incorporate partition information into tuple 
cache keys
......................................................................

IMPALA-13898: Incorporate partition information into tuple cache keys

Currently, the tuple cache keys do not include partition
information in either the planner key or the fragment instance
key. However, the partition actually is important to correctness.

First, there are settings defined on the table and partition that
can impact the results. For example, for processing text files,
the separator, escape character, etc are specified at the table
level. This impacts the rows produced from a given file. There
are other such settings stored at the partition level (e.g.
the JSON binary format).

Second, it is possible to have two partitions pointed at the same
filesystem location. For example, 
scale_db.num_partitions_1234_blocks_per_partition_1
is a table that has all partitions pointing to the same
location. In that case, the cache can't tell the partitions
apart based on the files alone. This is an exotic configuration.
Incorporating an identifier of the partition (e.g. the partition
keys/values) allows the cache to tell the difference.

To fix this, we incorporate partition information into the
key. At planning time, when incorporating the scan range information,
we also incorporate information about the associated partitions.
This moves the code to HdfsScanNode and changes it to iterate over
the partitions, hashing both the partition information and the scan
ranges. At runtime, the TupleCacheNode looks up the partition
associated with a scan node and hashes the additional information
on the HdfsPartitionDescriptor.

Testing:
 - Added a frontend test in TupleCacheTest for a table with
   multiple partitions pointed at the same place.
 - Added custom cluster tests testing both issues

Change-Id: I3a7109fcf8a30bf915bb566f7d642f8037793a8c
---
M be/src/exec/tuple-cache-node.cc
M be/src/exec/tuple-cache-node.h
M be/src/runtime/descriptors.cc
M be/src/runtime/descriptors.h
M fe/src/main/java/org/apache/impala/planner/HdfsScanNode.java
M fe/src/main/java/org/apache/impala/planner/TupleCacheInfo.java
M fe/src/test/java/org/apache/impala/planner/TupleCacheTest.java
M tests/common/impala_test_suite.py
M tests/custom_cluster/test_tuple_cache.py
9 files changed, 245 insertions(+), 54 deletions(-)



  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/74/23074/1
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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: I3a7109fcf8a30bf915bb566f7d642f8037793a8c
Gerrit-Change-Number: 23074
Gerrit-PatchSet: 1
Gerrit-Owner: Joe McDonnell <[email protected]>

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