TaskSupport

A trait implementing the scheduling of a parallel collection operation.

Parallel collections are modular in the way operations are scheduled. Each parallel collection is parametrized with a task support object which is responsible for scheduling and load-balancing tasks to processors.

A task support object can be changed in a parallel collection after it has been created, but only during a quiescent period, i.e. while there are no concurrent invocations to parallel collection methods.

There are currently a few task support implementations available for parallel collections. The scala.collection.parallel.ForkJoinTaskSupport uses a fork-join pool internally.

The scala.collection.parallel.ExecutionContextTaskSupport uses the default execution context implementation found in scala.concurrent, and it reuses the thread pool used in scala.concurrent.

The execution context task support is set to each parallel collection by default, so parallel collections reuse the same fork-join pool as the future API.

Here is a way to change the task support of a parallel collection:

import scala.collection.parallel._
val pc = mutable.ParArray(1, 2, 3)
pc.tasksupport = new ForkJoinTaskSupport(
  new scala.concurrent.forkjoin.ForkJoinPool(2))

See also: Configuring Parallel Collections section on the parallel collection's guide for more information.

Linear Supertypes

Tasks, AnyRef, Any

Known Subclasses

ExecutionContextTaskSupport, ForkJoinTaskSupport, ThreadPoolTaskSupport

Type Members

trait WrappedTask[R, +Tp] extends AnyRef

Definition Classes
Tasks

Abstract Value Members

abstract val environment: AnyRef

The type of the environment is more specific in the implementations.
The type of the environment is more specific in the implementations.

Definition Classes
Tasks
abstract def execute[R, Tp](fjtask: Task[R, Tp]): () ⇒ R

Executes a task and returns a future.
Executes a task and returns a future. Forwards an exception if some task threw it.

Definition Classes
Tasks
abstract def executeAndWaitResult[R, Tp](task: Task[R, Tp]): R

Executes a result task, waits for it to finish, then returns its result.
Executes a result task, waits for it to finish, then returns its result. Forwards an exception if some task threw it.

Definition Classes
Tasks
abstract def parallelismLevel: Int

Retrieves the parallelism level of the task execution environment.
Retrieves the parallelism level of the task execution environment.

Definition Classes
Tasks

Concrete Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def asInstanceOf[T0]: T0

Definition Classes
Any
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )

Related Doc: package parallel

trait TaskSupport extends Tasks

Type Members

trait WrappedTask[R, +Tp] extends AnyRef

Abstract Value Members

abstract val environment: AnyRef

abstract def execute[R, Tp](fjtask: Task[R, Tp]): () ⇒ R

abstract def executeAndWaitResult[R, Tp](task: Task[R, Tp]): R

abstract def parallelismLevel: Int

Concrete Value Members

final def !=(arg0: Any): Boolean

final def ##(): Int

final def ==(arg0: Any): Boolean

final def asInstanceOf[T0]: T0

def clone(): AnyRef

final def eq(arg0: AnyRef): Boolean

def equals(arg0: Any): Boolean

def finalize(): Unit

final def getClass(): Class[_]

def hashCode(): Int

final def isInstanceOf[T0]: Boolean

final def ne(arg0: AnyRef): Boolean

final def notify(): Unit

final def notifyAll(): Unit

final def synchronized[T0](arg0: ⇒ T0): T0

def toString(): String

final def wait(): Unit

final def wait(arg0: Long, arg1: Int): Unit

final def wait(arg0: Long): Unit

Inherited from Tasks

Inherited from AnyRef

Inherited from Any

Ungrouped