Tim Armstrong has uploaded a new patch set (#6). Change subject: IMPALA-4397,IMPALA-3259: reduce codegen time and memory ......................................................................
IMPALA-4397,IMPALA-3259: reduce codegen time and memory A handful of fixes to codegen memory usage: * Delete the IR module when we're done with it (it can be fairly large) * Track the compiled code size (typically not that large, but it can add up if there are many fragments). * Estimate optimisation memory requirements and track it in the memory tracker. This is very crude but much better than not tracking it. A handful of fixes to improve codegen time/cost, particularly targeted at compute stats workloads: * Avoid over-inlining when there are many aggregate functions, conjuncts, etc by adding "NoInline" attributes. * Bail of out text scanner codegen for wide tables. * Don't codegen non-grouping merge aggregations. They will only process one row per Impala daemon, so codegen is not worth it. * Make the Hll algorithm more efficient by specialising the hash function based on decimal width. Limitations: * This doesn't tackle over-inlining of large expr trees, but a similar approach will be used there in a follow-on patch. Perf: Compute stats on functional_parquet.widetable_1000_cols goes from 1min+ of codegen to < 1s codegen on my machine. Local perf runs of tpc-h and targeted perf showed no regressions and some moderate improvements (1-2%). Also did an experiment to understand the perf consequences of disabling inlining. I manually set CODEGEN_INLINE_EXPRS_THRESHOLD to 0, and ran: drop stats tpch_20_parquet.lineitem compute stats tpch_20_parquet.lineitem; There was no difference in time spent in the agg node: 30.7s with inlining, 30.5s without. Change-Id: Id10015b49da182cb181a653ac8464b4a18b71091 --- M be/src/benchmarks/hash-benchmark.cc M be/src/codegen/llvm-codegen-test.cc M be/src/codegen/llvm-codegen.cc M be/src/codegen/llvm-codegen.h M be/src/codegen/mcjit-mem-mgr.h M be/src/exec/aggregation-node.cc M be/src/exec/exchange-node.cc M be/src/exec/exec-node.cc M be/src/exec/exec-node.h M be/src/exec/hash-join-node.cc M be/src/exec/hash-table.cc M be/src/exec/hdfs-scan-node-base.cc M be/src/exec/hdfs-scanner.cc M be/src/exec/hdfs-scanner.h M be/src/exec/partitioned-aggregation-node.cc M be/src/exec/partitioned-hash-join-node.cc M be/src/exec/sort-node.cc M be/src/exec/topn-node.cc M be/src/exprs/aggregate-functions-ir.cc M be/src/exprs/anyval-util.h M be/src/exprs/expr-codegen-test.cc M be/src/exprs/expr.h M be/src/runtime/lib-cache.cc M be/src/runtime/runtime-state.cc M common/thrift/PlanNodes.thrift M fe/src/main/java/org/apache/impala/planner/DistributedPlanner.java M fe/src/main/java/org/apache/impala/planner/PlanNode.java M testdata/workloads/functional-query/queries/QueryTest/compute-stats.test M tests/query_test/test_aggregation.py 29 files changed, 1,465 insertions(+), 165 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/56/4956/6 -- To view, visit http://gerrit.cloudera.org:8080/4956 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: newpatchset Gerrit-Change-Id: Id10015b49da182cb181a653ac8464b4a18b71091 Gerrit-PatchSet: 6 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Tim Armstrong <tarmstr...@cloudera.com> Gerrit-Reviewer: Marcel Kornacker <mar...@cloudera.com> Gerrit-Reviewer: Michael Ho <k...@cloudera.com> Gerrit-Reviewer: Tim Armstrong <tarmstr...@cloudera.com>