Packages

c

org.apache.spark.sql.execution.adaptive

ReduceNumShufflePartitions

case class ReduceNumShufflePartitions(conf: SQLConf) extends Rule[SparkPlan] with Product with Serializable

A rule to adjust the post shuffle partitions based on the map output statistics.

The strategy used to determine the number of post-shuffle partitions is described as follows. To determine the number of post-shuffle partitions, we have a target input size for a post-shuffle partition. Once we have size statistics of all pre-shuffle partitions, we will do a pass of those statistics and pack pre-shuffle partitions with continuous indices to a single post-shuffle partition until adding another pre-shuffle partition would cause the size of a post-shuffle partition to be greater than the target size.

For example, we have two stages with the following pre-shuffle partition size statistics: stage 1: [100 MiB, 20 MiB, 100 MiB, 10MiB, 30 MiB] stage 2: [10 MiB, 10 MiB, 70 MiB, 5 MiB, 5 MiB] assuming the target input size is 128 MiB, we will have four post-shuffle partitions, which are:

  • post-shuffle partition 0: pre-shuffle partition 0 (size 110 MiB)
  • post-shuffle partition 1: pre-shuffle partition 1 (size 30 MiB)
  • post-shuffle partition 2: pre-shuffle partition 2 (size 170 MiB)
  • post-shuffle partition 3: pre-shuffle partition 3 and 4 (size 50 MiB)
Linear Supertypes
Serializable, Serializable, Product, Equals, Rule[SparkPlan], Logging, AnyRef, Any
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. ReduceNumShufflePartitions
  2. Serializable
  3. Serializable
  4. Product
  5. Equals
  6. Rule
  7. Logging
  8. AnyRef
  9. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. All

Instance Constructors

  1. new ReduceNumShufflePartitions(conf: SQLConf)

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. def apply(plan: SparkPlan): SparkPlan
    Definition Classes
    ReduceNumShufflePartitions → Rule
  5. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  6. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  7. val conf: SQLConf
  8. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  9. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  10. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  11. def initializeForcefully(isInterpreter: Boolean, silent: Boolean): Unit
    Definition Classes
    Logging
  12. def initializeLogIfNecessary(isInterpreter: Boolean, silent: Boolean): Boolean
    Attributes
    protected
    Definition Classes
    Logging
  13. def initializeLogIfNecessary(isInterpreter: Boolean): Unit
    Attributes
    protected
    Definition Classes
    Logging
  14. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  15. def isTraceEnabled(): Boolean
    Attributes
    protected
    Definition Classes
    Logging
  16. def log: Logger
    Attributes
    protected
    Definition Classes
    Logging
  17. def logDebug(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  18. def logDebug(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  19. def logError(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  20. def logError(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  21. def logInfo(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  22. def logInfo(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  23. def logName: String
    Attributes
    protected
    Definition Classes
    Logging
  24. def logTrace(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  25. def logTrace(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  26. def logWarning(msg: ⇒ String, throwable: Throwable): Unit
    Attributes
    protected
    Definition Classes
    Logging
  27. def logWarning(msg: ⇒ String): Unit
    Attributes
    protected
    Definition Classes
    Logging
  28. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  29. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  30. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  31. val ruleName: String
    Definition Classes
    Rule
  32. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  33. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  34. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  35. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()

Inherited from Serializable

Inherited from Serializable

Inherited from Product

Inherited from Equals

Inherited from Rule[SparkPlan]

Inherited from Logging

Inherited from AnyRef

Inherited from Any

Ungrouped