tmp

velox/exec/AggregateWindow.cpp

@@ -424,7 +424,8 @@ void registerAggregateWindowFunction(const std::string& name) {
               pool,
               stringAllocator,
               config);
-        });
+        },
+        exec::ProcessingUnit::kRow);
   }
 }
 } // namespace facebook::velox::exec

velox/exec/CMakeLists.txt

@@ -62,6 +62,7 @@ add_library(
   PlanNodeStats.cpp
   PrefixSort.cpp
   ProbeOperatorState.cpp
+  RowLevelStreamingWindowBuild.cpp
   RowContainer.cpp
   RowNumber.cpp
   SortBuffer.cpp

velox/exec/RowLevelStreamingWindowBuild.cpp

@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "velox/exec/RowLevelStreamingWindowBuild.h"
+
+namespace facebook::velox::exec {
+
+RowLevelStreamingWindowBuild::RowLevelStreamingWindowBuild(
+    const std::shared_ptr<const core::WindowNode>& windowNode,
+    velox::memory::MemoryPool* pool,
+    const common::SpillConfig* spillConfig,
+    tsan_atomic<bool>* nonReclaimableSection)
+    : WindowBuild(windowNode, pool, spillConfig, nonReclaimableSection) {}
+
+void RowLevelStreamingWindowBuild::buildNextInputOrPartition(bool isFinished) {
+  sortedRows_.push_back(inputRows_);
+  if (windowPartitions_.size() <= inputCurrentPartition_) {
+    auto partition =
+        folly::Range(sortedRows_.back().data(), sortedRows_.back().size());
+
+    windowPartitions_.push_back(std::make_shared<WindowPartition>(
+        data_.get(),
+        partition,
+        inputColumns_,
+        sortKeyInfo_,
+        ProcessingUnit::kRow));
+  }
+
+  windowPartitions_[inputCurrentPartition_]->insertNewBatch(sortedRows_.back());
+
+  if (isFinished) {
+    windowPartitions_[inputCurrentPartition_]->setTotalNum(
+        currentPartitionNum_ - 1);
+
+    inputCurrentPartition_++;
+    currentPartitionNum_ = 1;
+  }
+
+  inputRows_.clear();
+}
+
+void RowLevelStreamingWindowBuild::addInput(RowVectorPtr input) {
+  for (auto i = 0; i < inputChannels_.size(); ++i) {
+    decodedInputVectors_[i].decode(*input->childAt(inputChannels_[i]));
+  }
+
+  for (auto row = 0; row < input->size(); ++row) {
+    currentPartitionNum_++;
+    char* newRow = data_->newRow();
+
+    for (auto col = 0; col < input->childrenSize(); ++col) {
+      data_->store(decodedInputVectors_[col], row, newRow, col);
+    }
+
+    if (previousRow_ != nullptr &&
+        compareRowsWithKeys(previousRow_, newRow, partitionKeyInfo_)) {
+      buildNextInputOrPartition(true);
+    }
+
+    // Wait for the peers to be ready in single partition; these peers are the
+    // rows that have identical values in the ORDER BY clause.
+    if (previousRow_ != nullptr && inputRows_.size() > 0 &&
+        compareRowsWithKeys(previousRow_, newRow, sortKeyInfo_)) {
+      buildNextInputOrPartition(false);
+    }
+
+    inputRows_.push_back(newRow);
+    previousRow_ = newRow;
+  }
+}
+
+void RowLevelStreamingWindowBuild::noMoreInput() {
+  isFinished_ = true;
+  buildNextInputOrPartition(true);
+}
+
+std::shared_ptr<WindowPartition> RowLevelStreamingWindowBuild::nextPartition() {
+  return windowPartitions_[++outputCurrentPartition_];
+}
+
+bool RowLevelStreamingWindowBuild::hasNextPartition() {
+  return windowPartitions_.size() > 0 &&
+      outputCurrentPartition_ <= int(windowPartitions_.size() - 1);
+}
+
+} // namespace facebook::velox::exec

velox/exec/RowLevelStreamingWindowBuild.h

@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "velox/exec/WindowBuild.h"
+
+namespace facebook::velox::exec {
+
+/// Unlike StreamingWindowBuild, RowLevelStreamingWindowBuild is capable of
+/// processing window functions as rows arrive within a single partition,
+/// without the need to wait for the entire partition to be ready. This approach
+/// can significantly reduce memory usage, especially when a single partition
+/// contains a large amount of data. It is particularly suited for optimizing
+/// rank and row_number functions, as well as aggregate window functions with a
+/// default frame.
+class RowLevelStreamingWindowBuild : public WindowBuild {
+ public:
+  RowLevelStreamingWindowBuild(
+      const std::shared_ptr<const core::WindowNode>& windowNode,
+      velox::memory::MemoryPool* pool,
+      const common::SpillConfig* spillConfig,
+      tsan_atomic<bool>* nonReclaimableSection);
+
+  void addInput(RowVectorPtr input) override;
+
+  void spill() override {
+    VELOX_UNREACHABLE();
+  }
+
+  std::optional<common::SpillStats> spilledStats() const override {
+    return std::nullopt;
+  }
+
+  void noMoreInput() override;
+
+  bool hasNextPartition() override;
+
+  std::shared_ptr<WindowPartition> nextPartition() override;
+
+  bool needsInput() override {
+    // No partitions are available or the currentPartition is the last available
+    // one, so can consume input rows.
+    return windowPartitions_.size() == 0 ||
+        outputCurrentPartition_ == windowPartitions_.size() - 1;
+  }
+
+ private:
+  void buildNextInputOrPartition(bool isFinished);
+
+  /// Vector of pointers to each input row in the data_ RowContainer.
+  /// Rows are erased from data_ when they are processed in WindowPartition.
+  std::vector<std::vector<char*>> sortedRows_;
+
+  // Holds input rows within the current partition.
+  std::vector<char*> inputRows_;
+
+  // Used to compare rows based on partitionKeys.
+  char* previousRow_ = nullptr;
+
+  // Current partition being output. Used to return the WidnowPartitions.
+  vector_size_t outputCurrentPartition_ = -1;
+
+  bool isFinished_ = false;
+
+  // Current partition when adding input. Used to construct WindowPartitions.
+  vector_size_t inputCurrentPartition_ = 0;
+
+  std::vector<std::shared_ptr<WindowPartition>> windowPartitions_;
+
+  // Records the total rows number in each partition.
+  vector_size_t currentPartitionNum_ = 0;
+};
+
+} // namespace facebook::velox::exec

velox/exec/SortWindowBuild.cpp

@@ -291,7 +291,7 @@ void SortWindowBuild::loadNextPartitionFromSpill() {
   }
 }
 
-std::unique_ptr<WindowPartition> SortWindowBuild::nextPartition() {
+std::shared_ptr<WindowPartition> SortWindowBuild::nextPartition() {
   if (merge_ != nullptr) {
     VELOX_CHECK(!sortedRows_.empty(), "No window partitions available")
     auto partition = folly::Range(sortedRows_.data(), sortedRows_.size());
@@ -313,7 +313,7 @@ std::unique_ptr<WindowPartition> SortWindowBuild::nextPartition() {
   auto partition = folly::Range(
       sortedRows_.data() + partitionStartRows_[currentPartition_],
       partitionSize);
-  return std::make_unique<WindowPartition>(
+  return std::make_shared<WindowPartition>(
       data_.get(), partition, inputColumns_, sortKeyInfo_);
 }
 

velox/exec/SortWindowBuild.h

@@ -53,7 +53,7 @@ class SortWindowBuild : public WindowBuild {
 
   bool hasNextPartition() override;
 
-  std::unique_ptr<WindowPartition> nextPartition() override;
+  std::shared_ptr<WindowPartition> nextPartition() override;
 
  private:
   void ensureInputFits(const RowVectorPtr& input);

velox/exec/StreamingWindowBuild.cpp

@@ -60,7 +60,7 @@ void StreamingWindowBuild::noMoreInput() {
   partitionStartRows_.push_back(sortedRows_.size());
 }
 
-std::unique_ptr<WindowPartition> StreamingWindowBuild::nextPartition() {
+std::shared_ptr<WindowPartition> StreamingWindowBuild::nextPartition() {
   VELOX_CHECK_GT(
       partitionStartRows_.size(), 0, "No window partitions available")
 
@@ -89,7 +89,7 @@ std::unique_ptr<WindowPartition> StreamingWindowBuild::nextPartition() {
       sortedRows_.data() + partitionStartRows_[currentPartition_],
       partitionSize);
 
-  return std::make_unique<WindowPartition>(
+  return std::make_shared<WindowPartition>(
       data_.get(), partition, inputColumns_, sortKeyInfo_);
 }
 

velox/exec/StreamingWindowBuild.h

@@ -46,7 +46,7 @@ class StreamingWindowBuild : public WindowBuild {
 
   bool hasNextPartition() override;
 
-  std::unique_ptr<WindowPartition> nextPartition() override;
+  std::shared_ptr<WindowPartition> nextPartition() override;
 
   bool needsInput() override {
     // No partitions are available or the currentPartition is the last available

velox/exec/Window.cpp

@@ -15,6 +15,7 @@
  */
 #include "velox/exec/Window.h"
 #include "velox/exec/OperatorUtils.h"
+#include "velox/exec/RowLevelStreamingWindowBuild.h"
 #include "velox/exec/SortWindowBuild.h"
 #include "velox/exec/StreamingWindowBuild.h"
 #include "velox/exec/Task.h"
@@ -41,8 +42,13 @@ Window::Window(
   auto* spillConfig =
       spillConfig_.has_value() ? &spillConfig_.value() : nullptr;
   if (windowNode->inputsSorted()) {
-    windowBuild_ = std::make_unique<StreamingWindowBuild>(
-        windowNode, pool(), spillConfig, &nonReclaimableSection_);
+    if (supportRowLevelStreaming()) {
+      windowBuild_ = std::make_unique<RowLevelStreamingWindowBuild>(
+          windowNode_, pool(), spillConfig, &nonReclaimableSection_);
+    } else {
+      windowBuild_ = std::make_unique<StreamingWindowBuild>(
+          windowNode, pool(), spillConfig, &nonReclaimableSection_);
+    }
   } else {
     windowBuild_ = std::make_unique<SortWindowBuild>(
         windowNode, pool(), spillConfig, &nonReclaimableSection_, &spillStats_);
@@ -187,6 +193,31 @@ void Window::createWindowFunctions() {
   }
 }
 
+// The supportRowLevelStreaming is designed to support 'rank' and
+// 'row_number' functions and the agg window function with default frame.
+bool Window::supportRowLevelStreaming() {
+  for (const auto& windowNodeFunction : windowNode_->windowFunctions()) {
+    const auto& functionName = windowNodeFunction.functionCall->name();
+    auto windowFunctionEntry =
+        exec::getWindowFunctionEntry(functionName).value();
+    if (windowFunctionEntry->processingUnit == ProcessingUnit::kPartition) {
+      return false;
+    }
+
+    const auto& frame = windowNodeFunction.frame;
+    bool isDefaultFrame =
+        (frame.startType == core::WindowNode::BoundType::kUnboundedPreceding &&
+         frame.endType == core::WindowNode::BoundType::kCurrentRow);
+    // Only support the agg window function with default frame.
+    if (!(functionName == "rank" || functionName == "row_number") &&
+        !isDefaultFrame) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
 void Window::addInput(RowVectorPtr input) {
   windowBuild_->addInput(input);
   numRows_ += input->size();
@@ -474,7 +505,8 @@ void Window::computePeerAndFrameBuffers(
       // Ranking functions do not care about frames. So the function decides
       // further what to do with empty frames.
       computeValidFrames(
-          currentPartition_->numRows() - 1,
+          currentPartition_->numRows() -
+              currentPartition_->offsetInPartition() - 1,
           numRows,
           rawFrameStarts[i],
           rawFrameEnds[i],
@@ -543,7 +575,18 @@ vector_size_t Window::callApplyLoop(
           result);
       resultIndex += rowsForCurrentPartition;
       numOutputRowsLeft -= rowsForCurrentPartition;
-      callResetPartition();
+      if (currentPartition_->supportRowLevelStreaming()) {
+        if (currentPartition_->isFinished()) {
+          callResetPartition();
+        } else {
+          // Break until the next getOutput call to handle the remaining data in
+          // currentPartition_.
+          break;
+        }
+      } else {
+        callResetPartition();
+      }
+
       if (!currentPartition_) {
         // The WindowBuild doesn't have any more partitions to process right
         // now. So break until the next getOutput call.
@@ -585,6 +628,14 @@ RowVectorPtr Window::getOutput() {
     }
   }
 
+  // BuildNextBatch until all the rows in currentPartition finished.
+  if (currentPartition_->supportRowLevelStreaming() &&
+      partitionOffset_ == currentPartition_->numRows()) {
+    if (!currentPartition_->buildNextBatch()) {
+      return nullptr;
+    }
+  }
+
   auto numOutputRows = std::min(numRowsPerOutput_, numRowsLeft);
   auto result = BaseVector::create<RowVector>(
       outputType_, numOutputRows, operatorCtx_->pool());

velox/exec/Window.h

@@ -88,6 +88,8 @@ class Window : public Operator {
     const std::optional<FrameChannelArg> end;
   };
 
+  bool supportRowLevelStreaming();
+
   // Creates WindowFunction and frame objects for this operator.
   void createWindowFunctions();
 
@@ -165,7 +167,7 @@ class Window : public Operator {
 
   // Used to access window partition rows and columns by the window
   // operator and functions. This structure is owned by the WindowBuild.
-  std::unique_ptr<WindowPartition> currentPartition_;
+  std::shared_ptr<WindowPartition> currentPartition_;
 
   // HashStringAllocator required by functions that allocate out of line
   // buffers.

velox/exec/WindowBuild.h

@@ -68,7 +68,7 @@ class WindowBuild {
   // the underlying columns of Window partition data.
   // Check hasNextPartition() before invoking this function. This function fails
   // if called when no partition is available.
-  virtual std::unique_ptr<WindowPartition> nextPartition() = 0;
+  virtual std::shared_ptr<WindowPartition> nextPartition() = 0;
 
   // Returns the average size of input rows in bytes stored in the
   // data container of the WindowBuild.