Todd Lipcon has submitted this change and it was merged. ( http://gerrit.cloudera.org:8080/13661 )
Change subject: KUDU-2381: Optimize DeltaMemStore for case of no matching deltas. ...................................................................... KUDU-2381: Optimize DeltaMemStore for case of no matching deltas. Add a variable for lazy initialization to accelerate DeltaMemStore scan for case of no matching deltas. Rerun the benchmark of this patch with the original workload mentioned in the JIRA (select * from my_wide_table where c1=<value that does not occur>). Here are the top CPU consumers before and after: Before: + 20.39% kudu-tserver kudu-tserver [.] kudu::tablet::DeltaPreparer<kudu::tablet::DMSPreparerTraits>::Start(unsigned long, int) + 10.53% kudu-tserver kudu-tserver [.] kudu::tablet::CFileSet::Iterator::FinishBatch() + 8.64% kudu-tserver kudu-tserver [.] kudu::GetMemcmpableVarint64(kudu::Slice*, unsigned long*) + 7.35% kudu-tserver kudu-tserver [.] LZ4_decompress_fast After: + 12.41% kudu-tserver kudu-tserver [.] kudu::tablet::CFileSet::Iterator::FinishBatch() + 10.74% kudu-tserver kudu-tserver [.] kudu::GetMemcmpableVarint64(kudu::Slice*, unsigned long*) + 9.94% kudu-tserver kudu-tserver [.] LZ4_decompress_fast + 7.54% kudu-tserver kudu-tserver [.] kudu::tablet::DeltaFileIterator<(kudu::tablet::DeltaType)0>::AddDeltas(unsigned int, unsigned int) + 6.38% kudu-tserver kudu-tserver [.] bshuf_shuffle_bit_eightelem_AVX_avx2 + 6.03% kudu-tserver kudu-tserver [.] kudu::tablet::DeltaFileIterator<(kudu::tablet::DeltaType)0>::PrepareBatch(unsigned long, int) ... + 3.21% kudu-tserver kudu-tserver [.] kudu::tablet::DeltaPreparer<kudu::tablet::DeltaFilePreparerTraits<(kudu::tablet::DeltaType)0> >::Start(unsigned long, int) We can see DeltaPreparer::Start go from 20% CPU to 3% CPU. Change-Id: I799e81fef759d22f14d4530dbf0b250e0d7bc69b Reviewed-on: http://gerrit.cloudera.org:8080/13661 Tested-by: Kudu Jenkins Reviewed-by: Todd Lipcon <[email protected]> --- M src/kudu/tablet/delta_store.cc M src/kudu/tablet/delta_store.h 2 files changed, 29 insertions(+), 17 deletions(-) Approvals: Kudu Jenkins: Verified Todd Lipcon: Looks good to me, approved -- To view, visit http://gerrit.cloudera.org:8080/13661 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: kudu Gerrit-Branch: master Gerrit-MessageType: merged Gerrit-Change-Id: I799e81fef759d22f14d4530dbf0b250e0d7bc69b Gerrit-Change-Number: 13661 Gerrit-PatchSet: 4 Gerrit-Owner: ZhangYao <[email protected]> Gerrit-Reviewer: Kudu Jenkins (120) Gerrit-Reviewer: Todd Lipcon <[email protected]> Gerrit-Reviewer: Yao Xu <[email protected]> Gerrit-Reviewer: ZhangYao <[email protected]>
