nsivabalan commented on code in PR #7825:
URL: https://github.com/apache/hudi/pull/7825#discussion_r1094947575
##########
hudi-client/hudi-spark-client/src/main/scala/org/apache/hudi/HoodieDatasetBulkInsertHelper.scala:
##########
@@ -62,23 +64,18 @@ object HoodieDatasetBulkInsertHelper
partitioner: BulkInsertPartitioner[Dataset[Row]],
shouldDropPartitionColumns: Boolean): Dataset[Row]
= {
val populateMetaFields = config.populateMetaFields()
- val schema = df.schema
-
- val metaFields = Seq(
- StructField(HoodieRecord.COMMIT_TIME_METADATA_FIELD, StringType),
- StructField(HoodieRecord.COMMIT_SEQNO_METADATA_FIELD, StringType),
- StructField(HoodieRecord.RECORD_KEY_METADATA_FIELD, StringType),
- StructField(HoodieRecord.PARTITION_PATH_METADATA_FIELD, StringType),
- StructField(HoodieRecord.FILENAME_METADATA_FIELD, StringType))
- val updatedSchema = StructType(metaFields ++ schema.fields)
+ val schema = df.schema
+ val populatedSchema = addMetaFields(schema)
val updatedDF = if (populateMetaFields) {
val keyGeneratorClassName =
config.getStringOrThrow(HoodieWriteConfig.KEYGENERATOR_CLASS_NAME,
"Key-generator class name is required")
-
- val prependedRdd: RDD[InternalRow] =
- df.queryExecution.toRdd.mapPartitions { iter =>
+ val sourceRdd = df.queryExecution.toRdd
+ val populatedRdd: RDD[InternalRow] = if (hasMetaFields(schema)) {
Review Comment:
is this for clustering row writer code path ?
##########
hudi-client/hudi-spark-client/src/main/scala/org/apache/spark/sql/HoodieDataTypeUtils.scala:
##########
@@ -18,10 +18,29 @@
package org.apache.spark.sql
+import org.apache.hudi.common.model.HoodieRecord
import org.apache.spark.sql.types._
+import scala.jdk.CollectionConverters.collectionAsScalaIterableConverter
+
object HoodieDataTypeUtils {
+ /**
+ * Checks whether provided schema contains Hudi's meta-fields
+ *
+ * NOTE: This method validates presence of just one field
[[HoodieRecord.RECORD_KEY_METADATA_FIELD]],
+ * however assuming that meta-fields should either be omitted or specified
in full
+ */
+ def hasMetaFields(structType: StructType): Boolean =
+ structType.getFieldIndex(HoodieRecord.RECORD_KEY_METADATA_FIELD).isDefined
Review Comment:
minor. should we check for partition path as well ?
##########
hudi-client/hudi-spark-client/src/main/scala/org/apache/hudi/HoodieDatasetBulkInsertHelper.scala:
##########
@@ -220,4 +214,41 @@ object HoodieDatasetBulkInsertHelper
val keyGenerator = ReflectionUtils.loadClass(keyGeneratorClassName, new
TypedProperties(config.getProps)).asInstanceOf[BuiltinKeyGenerator]
keyGenerator.getPartitionPathFields.asScala
}
+
+ /**
+ * We use custom Spark [[Partitioner]] that is aware of the target table's
partitioning
+ * so that during inevitable shuffling required for de-duplication, we also
assign records
+ * into individual Spark partitions in a way affine with target table's
physical partitioning
+ * (ie records from the same table's partition will be co-located in the
same Spark's partition)
+ *
+ * This would allow us to
+ * <ul>
+ * <li>Save on additional shuffling subsequently (by
[[BulkInsertPartitioner]])</li>
+ * <li>Avoid "small files explosion" entailed by random (hash)
partitioning stemming
+ * from the fact that every Spark partition hosts records from many
table's partitions
+ * resulting into every Spark task writing into their own files in these
partitions (in
+ * case no subsequent re-partitioning is performed)
+ * </li>
+ * <ul>
+ *
+ * For more details check out HUDI-5685
+ */
+ private case class TablePartitioningAwarePartitioner(override val
numPartitions: Int) extends Partitioner {
+ override def getPartition(key: Any): Int = {
+ key match {
+ case null => 0
+ case (partitionPath, recordKey) =>
Review Comment:
won't this result in data skews? if one of the hudi partition has lot of
data, the respective spark partition will skew the total time for de-dup right?
##########
hudi-client/hudi-spark-client/src/main/scala/org/apache/hudi/HoodieDatasetBulkInsertHelper.scala:
##########
@@ -220,4 +214,41 @@ object HoodieDatasetBulkInsertHelper
val keyGenerator = ReflectionUtils.loadClass(keyGeneratorClassName, new
TypedProperties(config.getProps)).asInstanceOf[BuiltinKeyGenerator]
keyGenerator.getPartitionPathFields.asScala
}
+
+ /**
+ * We use custom Spark [[Partitioner]] that is aware of the target table's
partitioning
+ * so that during inevitable shuffling required for de-duplication, we also
assign records
+ * into individual Spark partitions in a way affine with target table's
physical partitioning
+ * (ie records from the same table's partition will be co-located in the
same Spark's partition)
+ *
+ * This would allow us to
+ * <ul>
+ * <li>Save on additional shuffling subsequently (by
[[BulkInsertPartitioner]])</li>
+ * <li>Avoid "small files explosion" entailed by random (hash)
partitioning stemming
+ * from the fact that every Spark partition hosts records from many
table's partitions
+ * resulting into every Spark task writing into their own files in these
partitions (in
+ * case no subsequent re-partitioning is performed)
+ * </li>
+ * <ul>
+ *
+ * For more details check out HUDI-5685
+ */
+ private case class TablePartitioningAwarePartitioner(override val
numPartitions: Int) extends Partitioner {
+ override def getPartition(key: Any): Int = {
+ key match {
+ case null => 0
+ case (partitionPath, recordKey) =>
Review Comment:
this was one of the reason why we did not go w/ this to avoid data skews.
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