Method getOutput

bolt/exec/TableScan.cpp:155–438

}

RowVectorPtr TableScan::getOutput() {
  SuspendedSection suspendedSection(driverCtx_->driver);
  auto exitCurStatusGuard = folly::makeGuard([this]() { curStatus_ = ""; });

  if (noMoreSplits_) {
    return nullptr;
  }

  const auto& queryConfig = operatorCtx_->task()->queryCtx()->queryConfig();

  curStatus_ = "getOutput: enter";
  const auto startTimeMs = getCurrentTimeMs();
  for (;;) {
    if (needNewSplit_) {
      // Check if our Task needs us to yield or we've been running for too long
      // w/o producing a result. In this case we return with the Yield blocking
      // reason and an already fulfilled future.
      curStatus_ = "getOutput: task->shouldStop";
      const StopReason taskStopReason = driverCtx_->task->shouldStop();
      if (shouldStop(taskStopReason) ||
          shouldYield(taskStopReason, startTimeMs)) {
        blockingReason_ = BlockingReason::kYield;
        blockingFuture_ = ContinueFuture{folly::Unit{}};
        // A point for test code injection.
        BOLT_TEST_ADJUST(
            "bytedance::bolt::exec::TableScan::getOutput::bail", this);
        return nullptr;
      }

      // A point for test code injection.
      BOLT_TEST_ADJUST("bytedance::bolt::exec::TableScan::getOutput", this);

      exec::Split split;
      curStatus_ = "getOutput: task->getSplitOrFuture";
      blockingReason_ = driverCtx_->task->getSplitOrFuture(
          driverCtx_->splitGroupId,
          planNodeId(),
          split,
          blockingFuture_,
          maxPreloadedSplits_,
          splitPreloader_);
      if (blockingReason_ != BlockingReason::kNotBlocked) {
        return nullptr;
      }

      if (!split.hasConnectorSplit()) {
        noMoreSplits_ = true;
        pendingDynamicFilters_.clear();
        if (dataSource_) {
          curStatus_ = "getOutput: noMoreSplits_=1, updating stats_";
          auto connectorStats = dataSource_->runtimeStats();
          auto lockedStats = stats_.wlock();
          if (connectorStats.count("rawBytesRead<4k") > 0) {
            LOG(INFO)
                << "IO pattern: "
                << "totalBytesRead: "
                << succinctBytes(connectorStats.at("rawBytesRead").value)
                << ", totalScanTime: "