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@dmitry-chirkov-dremio Based on our prior conversation, here are the benchmark measurements evaluating the direct prefix path versus the adaptive sampling heuristic on GH-55254. Benchmark Notes: Direct Prefix (Option A) vs. Adaptive Sampling (Option B)We evaluated the adaptive heuristic prototyping 32 evenly spaced sampled pairs per batch (triggering the prefix path on >= 4 sample rejections for mixed types, >= 8 for view/view, and falling back to the baseline executor below 4,096 rows): Comparative Benchmark Results:
Note: Symmetric operand order ( Takeaways:
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…gView equality kernels ### Rationale for this change In apache#55171, direct comparison kernels were added between StringView/BinaryView and offset-based string types. Those kernels relied on `applicator::ScalarBinary` with `ArrayIterator<BinaryViewType>`, which eagerly calls `util::FromBinaryView` and resolves variadic payload pointers for every element regardless of match outcome. As discussed in apache#55254, equality comparisons (`equal`, `not_equal`) can check the view's 4-byte inline prefix and string length before accessing payload buffers, rejecting mismatches early. ### What changes are included in this PR? 1. `util::EqualBinaryViewString`: Added in `arrow/util/binary_view_util.h` to compare a `BinaryViewType::c_type` with contiguous string data. It checks length and 4-byte prefix before dereferencing view variadic buffers. 2. Dedicated equality kernels: Implemented `ViewCompareViewEqual` and `ViewCompareStringEqual` in `scalar_compare.cc`, replacing eager iterator resolution for `equal` and `not_equal`. 3. Register-pinned scalar comparisons: For array-scalar operations, unpacked scalar length and prefix are pinned in registers outside the loop, avoiding repeated scalar lookups. 4. Tests: Extended `TestBinaryViewCompareKernel.ArrayArray` and `TestBinaryViewCompareKernel.ArrayScalar` with cases covering prefix mismatch, out-of-line equality, null bytes, and long strings. ### Are these changes tested? Yes, extended existing parameterized tests in `scalar_compare_test.cc`. ### Are there any user-facing changes? No. ### Was AI used for this PR? AI was used to assist with kernel registration and testing under human direction. **PR code and description written by:** - [ ] Human - [x] AI **Reviewed before submission by:** - [x] Human - [x] AI - [ ] Not reviewed * GitHub Issue: apache#55254
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…uality kernels - Extract shared ViewArrayCompareBinaryScalarEqual helper to decouple View and String kernel structs. - Optimize variadic payload comparisons by skipping the verified 4-byte prefix. - Use stateless indexed offset traversal in ViewCompareStringEqual::ArrayArray. - Clean up boolean expressions and add Doxygen API documentation in binary_view_util.h. - Add asymmetric slice test coverage in scalar_compare_test.cc.
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Rationale for this change
In #55171, direct comparison kernels were added between StringView/BinaryView and offset-based string types. Those kernels relied on
applicator::ScalarBinarywithArrayIterator<BinaryViewType>, which eagerly callsutil::FromBinaryViewand resolves variadic payload pointers for every element regardless of match outcome.As discussed in #55254, equality comparisons (
equal,not_equal) can check the view's 4-byte inline prefix and string length before accessing payload buffers, rejecting mismatches early.What changes are included in this PR?
util::EqualBinaryViewString: Added inarrow/util/binary_view_util.hto compare aBinaryViewType::c_typewith contiguous string data. It checks length and 4-byte prefix before dereferencing view variadic buffers.ViewCompareViewEqualandViewCompareStringEqualinscalar_compare.cc, replacing eager iterator resolution forequalandnot_equal.TestBinaryViewCompareKernel.ArrayArrayandTestBinaryViewCompareKernel.ArrayScalarwith cases covering prefix mismatch, out-of-line equality, null bytes, and long strings.Are these changes tested?
Yes, extended existing parameterized tests in
scalar_compare_test.cc.Are there any user-facing changes?
No.
Was AI used for this PR?
AI was used to assist with kernel registration and testing under human direction.
PR code and description written by:
Reviewed before submission by: