Method reserveMemory

bolt/exec/HashBuild.cpp:755–850

}

bool HashBuild::reserveMemory(
    const RowVectorPtr& input,
    SpilledRows spilledRows) {
  BOLT_CHECK(spillEnabled());

  Operator::ReclaimableSectionGuard guard(this);
  numSpillRows_ = 0;
  numSpillBytes_ = 0;

  auto* rows = table_->rows();
  const auto numRows = rows->numRows();

  auto [freeRows, outOfLineFreeBytes] = rows->freeSpace();
  const auto outOfLineBytes =
      rows->stringAllocator().retainedSize() - outOfLineFreeBytes;
  const auto outOfLineBytesPerRow =
      std::max<uint64_t>(1, numRows == 0 ? 0 : outOfLineBytes / numRows);
  const auto currentUsage = pool()->currentBytes();

  if (numRows != 0) {
    // Test-only spill path.
    if (testingTriggerSpill()) {
      numSpillRows_ = std::max<int64_t>(1, numRows / 10);
      numSpillBytes_ = numSpillRows_ * outOfLineBytesPerRow;
      return false;
    }

    // We check usage from the parent pool to take peers' allocations into
    // account.
    auto nodeUsage = pool()->currentBytes();
    // For hybrid join without scattered mode, include payload memory that
    // is not tracked by the pool but will be needed during coalesceBatches().
    if (hybridJoin_ && table_->hybridData() && !scatteredMode_) {
      nodeUsage += table_->hybridData()->payloadMemoryBytes();
    }
    if (spillMemoryThreshold_ != 0 && nodeUsage > spillMemoryThreshold_) {
      const int64_t bytesToSpill =
          nodeUsage * spillConfig()->spillableReservationGrowthPct / 100;
      numSpillRows_ = std::max<int64_t>(
          1, bytesToSpill / (rows->fixedRowSize() + outOfLineBytesPerRow));
      numSpillBytes_ = numSpillRows_ * outOfLineBytesPerRow;
      return false;
    }
  }
  bool rowBasedSpill = spilledRows.rows != nullptr;

  auto inputBytes =
      rowBasedSpill ? spilledRows.size : input->estimateFlatSize();
  auto inputNum = rowBasedSpill ? spilledRows.rows->size() : input->size();

  const auto minReservationBytes =
      currentUsage * spillConfig_->minSpillableReservationPct / 100;
  const auto availableReservationBytes = pool()->availableReservation();
  const auto tableIncrementBytes = table_->hashTableSizeIncrease(inputNum);
  const int64_t flatBytes = inputBytes;
  const auto rowContainerIncrementBytes = numRows == 0
      ? flatBytes * 2
      : rows->sizeIncrement(inputNum, outOfLineBytes > 0 ? flatBytes * 2 : 0);