combinable Class

Article
04/28/2015

The combinable<T> object is intended to provide thread-private copies of data, to perform lock-free thread-local sub-computations during parallel algorithms. At the end of the parallel operation, the thread-private sub-computations can then be merged into a final result. This class can be used instead of a shared variable, and can result in a performance improvement if there would otherwise be a lot of contention on that shared variable.

template<
   typename _Ty
>
class combinable;

Parameters

_Ty
The data type of the final merged result. The type must have a copy constructor and a default constructor.

Members

Public Constructors

Name	Description
combinable::combinable Constructor	Overloaded. Constructs a new combinable object.
combinable::~combinable Destructor	Destroys a combinable object.

Public Methods

Name	Description
combinable::clear Method	Clears any intermediate computational results from a previous usage.
combinable::combine Method	Computes a final value from the set of thread-local sub-computations by calling the supplied combine functor.
combinable::combine_each Method	Computes a final value from the set of thread-local sub-computations by calling the supplied combine functor once per thread-local sub-computation. The final result is accumulated by the function object.
combinable::local Method	Overloaded. Returns a reference to the thread-private sub-computation.

Public Operators

Name	Description
combinable::operator= Operator	Assigns to a combinable object from another combinable object.

Remarks

For more information, see Parallel Containers and Objects.

Inheritance Hierarchy

combinable

Requirements

Header: ppl.h

Namespace: concurrency