Impala Public Jenkins has submitted this change and it was merged. ( http://gerrit.cloudera.org:8080/24896 )
Change subject: IMPALA-15381: Reduce reservoir RNG state ...................................................................... IMPALA-15381: Reduce reservoir RNG state boost::mt19937_64 makes ReservoirSampleState 2536 bytes. FreePool rounds the allocation to 4 KiB, so sampling aggregates use 4624 bytes per function and group with their initial sample array. Use pcg32 to reduce the state to 48 bytes. The sampling sequence changes, so approximate results can change. Testing: - Full release build - HistogramTest.* - Large appx_median(), sample(), and histogram() queries - Updated the Init() allocation size in alloc-fail-init.test Change-Id: I9e046e3f0c1b91f1761ce578601a330bd864eb84 Assisted-by: gpt-5.6-sol (OpenAI Codex) Reviewed-on: http://gerrit.cloudera.org:8080/24896 Reviewed-by: Impala Public Jenkins <[email protected]> Tested-by: Impala Public Jenkins <[email protected]> --- M be/src/exprs/aggregate-functions-ir.cc M testdata/workloads/functional-query/queries/QueryTest/alloc-fail-init.test 2 files changed, 9 insertions(+), 13 deletions(-) Approvals: Impala Public Jenkins: Looks good to me, approved; Verified -- To view, visit http://gerrit.cloudera.org:8080/24896 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: merged Gerrit-Change-Id: I9e046e3f0c1b91f1761ce578601a330bd864eb84 Gerrit-Change-Number: 24896 Gerrit-PatchSet: 7 Gerrit-Owner: Aleksandr Efimov <[email protected]> Gerrit-Reviewer: Aleksandr Efimov <[email protected]> Gerrit-Reviewer: Csaba Ringhofer <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Joe McDonnell <[email protected]> Gerrit-Reviewer: Michael Smith <[email protected]> Gerrit-Reviewer: Riza Suminto <[email protected]>
