TPoolWorker< F, T, R > Class Template Reference

template<class F, class T = void, class R = void>
class TPoolWorker< F, T, R >

This class works together with TProcPool to allow the execution of functions in server processes.

Depending on the exact task that the worker is required to execute, a different version of the class can be called.

TPoolWorker<F, T, R>

The most general case, used by TProcPool::MapReduce(F func, T& args, R redfunc). This worker is build with:

• a function of signature F (the one to be executed)
• a collection of arguments of type T on which to apply the function
• a reduce function with signature R to be used to squash many returned values together.

Partial specializations

A few partial specializations are provided for less general cases:

• TPoolWorker<F, T, void> handles the case of a function that takes one argument and does not perform reduce operations (TProcPool::Map(F func, T& args)).
• TPoolWorker<F, void, R> handles the case of a function that takes no arguments, to be executed a specified amount of times, which returned values are squashed together (reduced) (TProcPool::Map(F func, unsigned nTimes, R redfunc))
• TPoolWorker<F, void, void> handles the case of a function that takes no arguments and whose arguments are not "reduced" (TProcPool::Map(F func, unsigned nTimes))

Since all the important data are passed to TPoolWorker at construction time, the kind of messages that client and workers have to exchange are usually very simple.

Definition at line 40 of file TPoolWorker.h.

Public Member Functions
	TPoolWorker (F func, const std::vector< T > &args, R redfunc)
	~TPoolWorker ()
void	HandleInput (MPCodeBufPair &msg)
	Handle a message with an EMPCode. More...
Public Member Functions inherited from TMPWorker
	TMPWorker ()
	Class constructor. More...
virtual	~TMPWorker ()
	TMPWorker (const TMPWorker &)=delete
TMPWorker &	operator= (const TMPWorker &)=delete
virtual void	Init (int fd, unsigned workerN)
	This method is called by children processes right after forking. More...
void	Run ()
TSocket *	GetSocket ()
pid_t	GetPid ()
unsigned	GetNWorker () const

Private Attributes
F	fFunc
	the function to be executed More...
std::vector< T >	fArgs
	a vector containing the arguments that must be passed to fFunc More...
R	fRedFunc
	the reduce function More...
decltype(fFunc(fArgs.front()))	fReducedResult
	the result of the execution More...
bool	fCanReduce
	true if fReducedResult can be reduced with a new result, false until we have produced one result More...

#include <TPoolWorker.h>

Inheritance diagram for TPoolWorker< F, T, R >:

Constructor & Destructor Documentation

template<class F, class T = void, class R = void>

TPoolWorker< F, T, R >::TPoolWorker ( F  func, const std::vector< T > &  args, R  redfunc  )

inline

Definition at line 45 of file TPoolWorker.h.

template<class F, class T = void, class R = void>

TPoolWorker< F, T, R >::~TPoolWorker ( )

inline

Definition at line 49 of file TPoolWorker.h.

Member Function Documentation

template<class F, class T = void, class R = void>

void TPoolWorker< F, T, R >::HandleInput ( MPCodeBufPair &  msg )

inlinevirtual

Handle a message with an EMPCode.

This method is called upon receiving a message with a code >= 1000 (i.e. EMPCode). It handles the most generic types of messages.
Classes inheriting from TMPWorker should implement their own HandleInput function, that should be able to handle codes specific to that application.
The appropriate version of the HandleInput method (TMPWorker's or the overriding version) is automatically called depending on the message code.

Parameters

msg	Execute instructions received from a TProcPool client

Reimplemented from TMPWorker.

Definition at line 51 of file TPoolWorker.h.

Member Data Documentation

template<class F, class T = void, class R = void>

std::vector<T> TPoolWorker< F, T, R >::fArgs

private

a vector containing the arguments that must be passed to fFunc

Definition at line 80 of file TPoolWorker.h.

Referenced by TPoolWorker< F, T, R >::HandleInput(), and TPoolWorker< F, T, void >::HandleInput().

template<class F, class T = void, class R = void>

bool TPoolWorker< F, T, R >::fCanReduce

private

true if fReducedResult can be reduced with a new result, false until we have produced one result

Definition at line 83 of file TPoolWorker.h.

Referenced by TPoolWorker< F, T, R >::HandleInput().

template<class F, class T = void, class R = void>

F TPoolWorker< F, T, R >::fFunc

private

the function to be executed

Definition at line 79 of file TPoolWorker.h.

Referenced by TPoolWorker< F, T, R >::HandleInput(), TPoolWorker< F, void, R >::HandleInput(), and TPoolWorker< F, T, void >::HandleInput().

template<class F, class T = void, class R = void>

R TPoolWorker< F, T, R >::fRedFunc

private

the reduce function

Definition at line 81 of file TPoolWorker.h.

Referenced by TPoolWorker< F, T, R >::HandleInput(), and TPoolWorker< F, void, R >::HandleInput().

template<class F, class T = void, class R = void>

decltype(fFunc(fArgs.front())) TPoolWorker< F, T, R >::fReducedResult

private

the result of the execution

Definition at line 82 of file TPoolWorker.h.

Referenced by TPoolWorker< F, T, R >::HandleInput(), and TPoolWorker< F, void, R >::HandleInput().

Collaboration diagram for TPoolWorker< F, T, R >:

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The documentation for this class was generated from the following file:

• core/multiproc/inc/TPoolWorker.h