Optimize FlatVector<T>::copyRanges (#6566)

Summary: Pull Request resolved: #6566 FlatVector::copyRanges is slow when there are many small ranges. I noticed this while investigating slowness of array_constructor which used created 1-row ranges: #5958 (comment) ``` FlatVector.h void copyRanges( const BaseVector* source, const folly::Range<const BaseVector::CopyRange*>& ranges) override { for (auto& range : ranges) { copy(source, range.targetIndex, range.sourceIndex, range.count); } } ``` This change optimizes FlatVector<T>::copyRanges using code from copy(source, targetIndex, sourceIndex, count) which copies one range. This change also replaces the latter call with a call to copyRanges, hence, the overall amount of code is about the same. An earlier change optimized array_constructor to not use copyRanges for primitive types, but it is still used by Array/MapVector::copyRanges, although, these do not create 1-row ranges. Still the array_constructor benchmark shows some wins for arrays and maps. ``` Before: array_constructor_ARRAY_nullfree##2_const 54.31ms 18.41 array_constructor_ARRAY_nulls##1 33.50ms 29.85 array_constructor_ARRAY_nulls##2 59.05ms 16.93 array_constructor_ARRAY_nulls##3 88.36ms 11.32 array_constructor_ARRAY_nulls##2_null 74.53ms 13.42 array_constructor_ARRAY_nulls##2_const 102.54ms 9.75 After: array_constructor_ARRAY_nullfree##2_const 41.36ms 24.18 array_constructor_ARRAY_nulls##1 30.51ms 32.78 array_constructor_ARRAY_nulls##2 55.13ms 18.14 array_constructor_ARRAY_nulls##3 77.93ms 12.83 array_constructor_ARRAY_nulls##2_null 68.84ms 14.53 array_constructor_ARRAY_nulls##2_const 83.91ms 11.92 Before: array_constructor_MAP_nullfree##2_const 67.44ms 14.83 array_constructor_MAP_nulls##1 37.00ms 27.03 array_constructor_MAP_nulls##2 67.76ms 14.76 array_constructor_MAP_nulls##3 100.88ms 9.91 array_constructor_MAP_nulls##2_null 84.22ms 11.87 array_constructor_MAP_nulls##2_const 122.55ms 8.16 After: array_constructor_MAP_nullfree##2_const 49.94ms 20.03 array_constructor_MAP_nulls##1 34.34ms 29.12 array_constructor_MAP_nulls##2 55.23ms 18.11 array_constructor_MAP_nulls##3 82.64ms 12.10 array_constructor_MAP_nulls##2_null 70.74ms 14.14 array_constructor_MAP_nulls##2_const 88.13ms 11.35 ``` Differential Revision: D49269500 fbshipit-source-id: 054dcec94cc3768443440ffb57d58c96f9b1f006
facebookincubator · Sep 18, 2023 · ab29e53 · ab29e53
1 parent 2857dff
commit ab29e53
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Showing 6 changed files with 203 additions and 209 deletions.
diff --git a/velox/vector/BaseVector.cpp b/velox/vector/BaseVector.cpp
@@ -334,6 +334,29 @@ VectorPtr BaseVector::createInternal(
   }
 }
 
+// static
+void BaseVector::setNulls(
+    uint64_t* rawNulls,
+    const folly::Range<const CopyRange*>& ranges,
+    bool isNull) {
+  const auto nullBits = isNull ? bits::kNull : bits::kNotNull;
+  applyToEachRange(
+      ranges, [&](auto targetIndex, auto /*sourceIndex*/, auto count) {
+        bits::fillBits(rawNulls, targetIndex, targetIndex + count, nullBits);
+      });
+}
+
+// static
+void BaseVector::copyNulls(
+    uint64_t* targetRawNulls,
+    const uint64_t* sourceRawNulls,
+    const folly::Range<const CopyRange*>& ranges) {
+  applyToEachRange(ranges, [&](auto targetIndex, auto sourceIndex, auto count) {
+    bits::copyBits(
+        sourceRawNulls, sourceIndex, targetRawNulls, targetIndex, count);
+  });
+}
+
 void BaseVector::addNulls(const uint64_t* bits, const SelectivityVector& rows) {
   VELOX_CHECK(isNullsWritable());
   VELOX_CHECK(length_ >= rows.end());

diff --git a/velox/vector/BaseVector.h b/velox/vector/BaseVector.h
@@ -371,6 +371,25 @@ class BaseVector {
         nulls_->asMutable<uint64_t>(), idx, bits::kNull ? value : !value);
   }
 
+  struct CopyRange {
+    vector_size_t sourceIndex;
+    vector_size_t targetIndex;
+    vector_size_t count;
+  };
+
+  /// Sets null flags for each row in 'ranges' to 'isNull'.
+  static void setNulls(
+      uint64_t* rawNulls,
+      const folly::Range<const CopyRange*>& ranges,
+      bool isNull);
+
+  /// Copies null flags for each row in 'ranges' from 'sourceRawNulls' to
+  /// 'targetRawNulls'.
+  static void copyNulls(
+      uint64_t* targetRawNulls,
+      const uint64_t* sourceRawNulls,
+      const folly::Range<const CopyRange*>& ranges);
+
   static int32_t
   countNulls(const BufferPtr& nulls, vector_size_t begin, vector_size_t end) {
     return nulls ? bits::countNulls(nulls->as<uint64_t>(), begin, end) : 0;
@@ -437,12 +456,6 @@ class BaseVector {
     copyRanges(source, folly::Range(&range, 1));
   }
 
-  struct CopyRange {
-    vector_size_t sourceIndex;
-    vector_size_t targetIndex;
-    vector_size_t count;
-  };
-
   /// Converts SelectivityVetor into a list of CopyRanges having sourceIndex ==
   /// targetIndex. Aims to produce as few ranges as possible. If all rows are
   /// selected, returns a single range.
@@ -906,6 +919,32 @@ class BaseVector {
   bool memoDisabled_{false};
 };
 
+/// Loops over rows in 'ranges' and invokes 'func' for each row.
+/// @param TFunc A void function taking two arguments: targetIndex and
+/// sourceIndex.
+template <typename TFunc>
+void applyToEachRow(
+    const folly::Range<const BaseVector::CopyRange*>& ranges,
+    const TFunc& func) {
+  for (const auto& range : ranges) {
+    for (auto i = 0; i < range.count; ++i) {
+      func(range.targetIndex + i, range.sourceIndex + i);
+    }
+  }
+}
+
+/// Loops over 'ranges' and invokes 'func' for each range.
+/// @param TFunc A void function taking 3 arguments: targetIndex, sourceIndex
+/// and count.
+template <typename TFunc>
+void applyToEachRange(
+    const folly::Range<const BaseVector::CopyRange*>& ranges,
+    const TFunc& func) {
+  for (const auto& range : ranges) {
+    func(range.targetIndex, range.sourceIndex, range.count);
+  }
+}
+
 template <>
 uint64_t BaseVector::byteSize<bool>(vector_size_t count);
 

diff --git a/velox/vector/ComplexVector.cpp b/velox/vector/ComplexVector.cpp
@@ -299,20 +299,17 @@ void RowVector::copyRanges(
   }
 
   if (isAllNullVector(*source)) {
-    for (const auto& range : ranges) {
-      for (auto i = 0; i < range.count; ++i) {
-        setNull(range.targetIndex + i, true);
-      }
-    }
+    BaseVector::setNulls(mutableRawNulls(), ranges, true);
     return;
   }
 
   auto minTargetIndex = std::numeric_limits<vector_size_t>::max();
   auto maxTargetIndex = std::numeric_limits<vector_size_t>::min();
-  for (auto& r : ranges) {
-    minTargetIndex = std::min(minTargetIndex, r.targetIndex);
-    maxTargetIndex = std::max(maxTargetIndex, r.targetIndex + r.count);
-  }
+  applyToEachRange(ranges, [&](auto targetIndex, auto sourceIndex, auto count) {
+    minTargetIndex = std::min(minTargetIndex, targetIndex);
+    maxTargetIndex = std::max(maxTargetIndex, targetIndex + count);
+  });
+
   SelectivityVector rows(maxTargetIndex);
   rows.setValidRange(0, minTargetIndex, false);
   rows.updateBounds();
@@ -324,11 +321,7 @@ void RowVector::copyRanges(
   DecodedVector decoded(*source);
   if (decoded.isIdentityMapping() && !decoded.mayHaveNulls()) {
     if (rawNulls_) {
-      auto* rawNulls = mutableRawNulls();
-      for (auto& r : ranges) {
-        bits::fillBits(
-            rawNulls, r.targetIndex, r.targetIndex + r.count, bits::kNotNull);
-      }
+      setNulls(mutableRawNulls(), ranges, false);
     }
     auto* rowSource = source->loadedVector()->as<RowVector>();
     for (int i = 0; i < children_.size(); ++i) {
@@ -337,27 +330,26 @@ void RowVector::copyRanges(
   } else {
     std::vector<BaseVector::CopyRange> baseRanges;
     baseRanges.reserve(ranges.size());
-    for (auto& r : ranges) {
-      for (vector_size_t i = 0; i < r.count; ++i) {
-        bool isNull = decoded.isNullAt(r.sourceIndex + i);
-        setNull(r.targetIndex + i, isNull);
-        if (isNull) {
-          continue;
-        }
-        auto baseIndex = decoded.index(r.sourceIndex + i);
-        if (!baseRanges.empty() &&
-            baseRanges.back().sourceIndex + 1 == baseIndex &&
-            baseRanges.back().targetIndex + 1 == r.targetIndex + i) {
-          ++baseRanges.back().count;
-        } else {
-          baseRanges.push_back({
-              .sourceIndex = baseIndex,
-              .targetIndex = r.targetIndex + i,
-              .count = 1,
-          });
-        }
+    applyToEachRow(ranges, [&](auto targetIndex, auto sourceIndex) {
+      bool isNull = decoded.isNullAt(sourceIndex);
+      setNull(targetIndex, isNull);
+      if (isNull) {
+        return;
       }
-    }
+      auto baseIndex = decoded.index(sourceIndex);
+      if (!baseRanges.empty() &&
+          baseRanges.back().sourceIndex + 1 == baseIndex &&
+          baseRanges.back().targetIndex + 1 == targetIndex) {
+        ++baseRanges.back().count;
+      } else {
+        baseRanges.push_back({
+            .sourceIndex = baseIndex,
+            .targetIndex = targetIndex,
+            .count = 1,
+        });
+      }
+    });
+
     auto* rowSource = decoded.base()->as<RowVector>();
     for (int i = 0; i < children_.size(); ++i) {
       children_[i]->copyRanges(
@@ -463,11 +455,7 @@ void ArrayVectorBase::copyRangesImpl(
     VectorPtr* targetValues,
     VectorPtr* targetKeys) {
   if (isAllNullVector(*source)) {
-    for (const auto& range : ranges) {
-      for (auto i = 0; i < range.count; ++i) {
-        setNull(range.targetIndex + i, true);
-      }
-    }
+    BaseVector::setNulls(mutableRawNulls(), ranges, true);
     return;
   }
 
@@ -537,46 +525,43 @@ void ArrayVectorBase::copyRangesImpl(
   } else {
     std::vector<CopyRange> outRanges;
     vector_size_t totalCount = 0;
-    for (auto& range : ranges) {
-      if (range.count == 0) {
-        continue;
-      }
-      VELOX_DCHECK(BaseVector::length_ >= range.targetIndex + range.count);
-      totalCount += range.count;
-    }
-    outRanges.reserve(totalCount);
-    for (auto& range : ranges) {
-      for (vector_size_t i = 0; i < range.count; ++i) {
-        if (source->isNullAt(range.sourceIndex + i)) {
-          setNull(range.targetIndex + i, true);
-        } else {
-          if (setNotNulls) {
-            setNull(range.targetIndex + i, false);
+    applyToEachRange(
+        ranges, [&](auto targetIndex, auto sourceIndex, auto count) {
+          if (count > 0) {
+            VELOX_DCHECK(BaseVector::length_ >= targetIndex + count);
+            totalCount += count;
           }
-          vector_size_t wrappedIndex =
-              source->wrappedIndex(range.sourceIndex + i);
-          vector_size_t copySize = sourceArray->sizeAt(wrappedIndex);
-
-          if (copySize > 0) {
-            auto copyOffset = sourceArray->offsetAt(wrappedIndex);
-
-            // If we're copying two adjacent ranges, merge them.  This only
-            // works if they're consecutive.
-            if (!outRanges.empty() &&
-                (outRanges.back().sourceIndex + outRanges.back().count ==
-                 copyOffset)) {
-              outRanges.back().count += copySize;
-            } else {
-              outRanges.push_back({copyOffset, childSize, copySize});
-            }
+        });
+    outRanges.reserve(totalCount);
+    applyToEachRow(ranges, [&](auto targetIndex, auto sourceIndex) {
+      if (source->isNullAt(sourceIndex)) {
+        setNull(targetIndex, true);
+      } else {
+        if (setNotNulls) {
+          setNull(targetIndex, false);
+        }
+        auto wrappedIndex = source->wrappedIndex(sourceIndex);
+        auto copySize = sourceArray->sizeAt(wrappedIndex);
+
+        if (copySize > 0) {
+          auto copyOffset = sourceArray->offsetAt(wrappedIndex);
+
+          // If we're copying two adjacent ranges, merge them.  This only
+          // works if they're consecutive.
+          if (!outRanges.empty() &&
+              (outRanges.back().sourceIndex + outRanges.back().count ==
+               copyOffset)) {
+            outRanges.back().count += copySize;
+          } else {
+            outRanges.push_back({copyOffset, childSize, copySize});
           }
-
-          mutableOffsets[range.targetIndex + i] = childSize;
-          mutableSizes[range.targetIndex + i] = copySize;
-          childSize += copySize;
         }
+
+        mutableOffsets[targetIndex] = childSize;
+        mutableSizes[targetIndex] = copySize;
+        childSize += copySize;
       }
-    }
+    });
 
     targetValues->get()->resize(childSize);
     targetValues->get()->copyRanges(sourceValues, outRanges);