Thomas Tauber-Marshall has uploaded a new patch set (#6). Change subject: IMPALA-5498: Support for partial sorts ......................................................................
IMPALA-5498: Support for partial sorts Impala currently supports total sorts (the entire set of data is sorted) and top-n sorts (only the highest/lowest n elements are sorted). This patch adds the ability to do partial sorts, where the data is divided up into some number of subsets, each of which is sorted individually. It accomplishes this by adding a new exec node, PartialSortNode. When PartialSortNode::GetNext() is called, it retrieves input up to its memory limit, uses the existing Sorter class to sort it, and outputs it. This is faster than a total sort with SortNode as it avoids the need to spill if the input is larger than the memory limit. Future work will look into setting a more restrictive memory limit on the PartialSortNode. In the planner, the SortNode plan node is used, with an enum value indicating if it is a total or partial sort. Adds a new counter 'RunSize' to the runtime profile which tracks the min, max, and avg size of the generated runs, in tuples. As a first use case, partial sort is used where a total sort was used previously for inserts into Kudu. Testing: - E2E test with a large INSERT into a Kudu table with a mem limit. Checks that no spills occurred. - Updated planner tests. - Existing E2E tests and stress test verify correctness of INSERT. - Perf tests on the 10 node cluster: inserting tpch_100.lineitem into a Kudu table with mem_limit=3gb: Previously: 5 runs are spilled, sort took 7m33s Now: no spills, sort takes 6m19s, for ~18% speedup Change-Id: Ieec2a15a0cc5240b1c13682067ab64670d1e0a38 --- M be/src/exec/CMakeLists.txt M be/src/exec/exec-node.cc A be/src/exec/partial-sort-node.cc A be/src/exec/partial-sort-node.h M be/src/exec/sort-node.h M be/src/runtime/sorter.cc M be/src/runtime/sorter.h M be/src/util/runtime-profile-counters.h M common/thrift/PlanNodes.thrift M fe/src/main/java/org/apache/impala/planner/AnalyticPlanner.java M fe/src/main/java/org/apache/impala/planner/Planner.java M fe/src/main/java/org/apache/impala/planner/SingleNodePlanner.java M fe/src/main/java/org/apache/impala/planner/SortNode.java M testdata/workloads/functional-planner/queries/PlannerTest/kudu-upsert.test M testdata/workloads/functional-planner/queries/PlannerTest/kudu.test M testdata/workloads/functional-query/queries/QueryTest/kudu_insert.test 16 files changed, 460 insertions(+), 67 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/67/7267/6 -- To view, visit http://gerrit.cloudera.org:8080/7267 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: newpatchset Gerrit-Change-Id: Ieec2a15a0cc5240b1c13682067ab64670d1e0a38 Gerrit-PatchSet: 6 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Thomas Tauber-Marshall <tmarsh...@cloudera.com> Gerrit-Reviewer: Dan Hecht <dhe...@cloudera.com> Gerrit-Reviewer: Matthew Jacobs <m...@cloudera.com> Gerrit-Reviewer: Mostafa Mokhtar <mmokh...@cloudera.com> Gerrit-Reviewer: Thomas Tauber-Marshall <tmarsh...@cloudera.com> Gerrit-Reviewer: Tim Armstrong <tarmstr...@cloudera.com> Gerrit-Reviewer: Zach Amsden <zams...@cloudera.com>
