Files
impala/tests/util
Thomas Tauber-Marshall 2510fe0aa0 IMPALA-4252: Min-max runtime filters for Kudu
This patch implements min-max filters for runtime filters. Each
runtime filter generates a bloom filter or a min-max filter,
depending on if it has HDFS or Kudu targets, respectively.

In RuntimeFilterGenerator in the planner, each hash join node
generates a bloom and min-max filter for each equi-join predicate, but
only those filters that end up being assigned to a target make it into
the final plan.

Min-max filters are only assigned to Kudu scans if the target expr is
a column, as Kudu doesn't support bounds on general exprs, and only if
the join op is '=' and not 'is distinct from', as Kudu doesn't support
returning NULLs if a bound is set.

Min-max filters are inserted into by the PartitionedHashJoinBuilder.
Codegen is used to eliminate branching on the type of filter. String
min-max filters truncate their bounds at 1024 chars, so that the max
amount of memory used by min-max filters is negligible.

For now, min-max filters are only applied at the KuduScanner, which
passes them into the Kudu client.

Future work will address applying min-max filters at HDFS scan nodes
and applying bloom filters at Kudu scan nodes.

Functional Testing:
- Added new planner tests and updated the old ones. (in old tests, a
  lot of runtime filters are renumbered as we always generate min-max
  filters even if they don't end up getting assigned and they take up
  some of the RF ids).
- Updated existing runtime filter tests to work with Kudu.
- Added e2e tests for min-max filter specific functionality.

Perf Testing:
- All tests run on Kudu stress cluster (10 nodes) and tpch_100_kudu,
  timings are averages of 3 runs.
- Ran a contrived query with a filter that does not eliminate any rows
  (full self join of lineitem). The difference in running time was
  negligible - 24.46s with filters on, 24.15s with filters off for
  a ~1% slowdown.
- Ran a contrived query with a filter that elimiates all rows (self
  join on lineitem with a join condition that never matches). The
  filters resulted in a significant speedup - 0.26s with filters on,
  1.46s with filters off for a ~5.6x speedup. This query is added to
  targeted-perf.

Change-Id: I02bad890f5b5f78388a3041bf38f89369b5e2f1c
Reviewed-on: http://gerrit.cloudera.org:8080/7793
Reviewed-by: Thomas Tauber-Marshall <tmarshall@cloudera.com>
Tested-by: Impala Public Jenkins
2017-11-17 21:33:51 +00:00
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