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

This class works together with TProcessExecutor 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 TProcessExecutor::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 (TProcessExecutor::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) (TProcessExecutor::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" (TProcessExecutor::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 77 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 constructors. More...

	TMPWorker (const std::vector< std::string > &fileNames, const std::string &treeName, unsigned nWorkers, ULong64_t maxEntries)

	TMPWorker (TTree *tree, unsigned nWorkers, ULong64_t maxEntries)

	TMPWorker (const TMPWorker &)=delete

virtual	~TMPWorker ()

unsigned	GetNWorker () const

pid_t	GetPid ()

TSocket *	GetSocket ()

virtual void	Init (int fd, unsigned workerN)
	This method is called by children processes right after forking. More...

TMPWorker &	operator= (const TMPWorker &)=delete

void	Run ()

Private Attributes
std::vector< T >	fArgs
	a vector containing the arguments that must be passed to fFunc More...

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

F	fFunc
	the function to be executed More...

R	fRedFunc
	the reduce function More...

decltype(fFunc(fArgs.front()))	fReducedResult
	the result of the execution More...

Additional Inherited Members
Protected Member Functions inherited from TMPWorker
void	CloseFile ()
	Handle file closing. More...

TFile *	OpenFile (const std::string &fileName)
	Handle file opening. More...

TTree *	RetrieveTree (TFile *fp)
	Retrieve a tree from an open file. More...

void	SendError (const std::string &errmsg, unsigned int code=MPCode::kError)
	Error sender. More...

void	Setup ()
	Auxilliary method for common initializations. More...

void	SetupTreeCache (TTree *tree)
	Tree cache handling. More...

Protected Attributes inherited from TMPWorker
TFile *	fFile
	last open file More...

std::vector< std::string >	fFileNames
	the files to be processed by all workers More...

std::string	fId
	identifier string in the form W<nwrk>\|P<proc id>=""> More...

ULong64_t	fMaxNEntries
	the maximum number of entries to be processed by this worker More...

unsigned	fNWorkers
	the number of workers spawned More...

ULong64_t	fProcessedEntries
	the number of entries processed by this worker so far More...

TTree *	fTree
	pointer to the tree to be processed. It is only used if the tree is directly passed to TProcessExecutor::Process as argument More...

std::string	fTreeName
	the name of the tree to be processed More...

#include <TPoolWorker.h>

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

[legend]

Constructor & Destructor Documentation

◆ TPoolWorker()

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 82 of file TPoolWorker.h.

◆ ~TPoolWorker()

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

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

inline

Definition at line 86 of file TPoolWorker.h.

Member Function Documentation

◆ HandleInput()

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 TProcessExecutor client

Reimplemented from TMPWorker.

Definition at line 88 of file TPoolWorker.h.

Member Data Documentation

◆ fArgs

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 119 of file TPoolWorker.h.

◆ fCanReduce

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 122 of file TPoolWorker.h.

◆ fFunc

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

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

private

the function to be executed

Definition at line 118 of file TPoolWorker.h.

◆ fRedFunc

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

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

private

the reduce function

Definition at line 120 of file TPoolWorker.h.

◆ fReducedResult

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 121 of file TPoolWorker.h.

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

core/multiproc/inc/TPoolWorker.h

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

TPoolWorker<F, T, R>

Partial specializations

Public Member Functions

Private Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ TPoolWorker()

◆ ~TPoolWorker()

Member Function Documentation

◆ HandleInput()

Member Data Documentation

◆ fArgs

◆ fCanReduce

◆ fFunc

◆ fRedFunc

◆ fReducedResult

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