SPARK中 会对Scan的小文件做合并到一个Task去处理么？

    val splitFiles = selectedPartitions.flatMap { partition =>
      partition.files.flatMap { file =>
        // getPath() is very expensive so we only want to call it once in this block:
        val filePath = file.getPath
        val isSplitable = relation.fileFormat.isSplitable(
          relation.sparkSession, relation.options, filePath)
        PartitionedFileUtil.splitFiles(
          sparkSession = relation.sparkSession,
          file = file,
          filePath = filePath,
          isSplitable = isSplitable,
          maxSplitBytes = maxSplitBytes,
          partitionValues = partition.values
        )
      }
    }.sortBy(_.length)(implicitly[Ordering[Long]].reverse)
    val partitions =
      FilePartition.getFilePartitions(relation.sparkSession, splitFiles, maxSplitBytes)
   new FileScanRDD(fsRelation.sparkSession, readFile, partitions)

...
 partitionedFiles.foreach { file =>
      if (currentSize + file.length > maxSplitBytes) {
        closePartition()
      }
      // Add the given file to the current partition.
      currentSize += file.length + openCostInBytes
      currentFiles += file
 }
...