wrench::ParallelModel Class Reference

A virtual class (with convenient static methods) to define parallel task performance models. More...

#include <ParallelModel.h>

Inheritance diagram for wrench::ParallelModel:

Public Member Functions
virtual std::vector< double >	getWorkPerThread (double total_work, unsigned long num_threads)=0
	A method the, for this parallel model, computes how much work each thread that is part of a parallel task should do. More...

Static Public Member Functions
static std::shared_ptr< ParallelModel >	AMDAHL (double alpha)
	Create an instance of an "Amdahl" parallel model. More...
static std::shared_ptr< ParallelModel >	CONSTANTEFFICIENCY (double efficiency)
	Create an instance of a "Constant Efficiency" parallel model. More...
static std::shared_ptr< ParallelModel >	CUSTOM (std::function< std::vector< double >(double, long)> lambda)
	Create an instance of a "Custom" parallel model. More...

Detailed Description

A virtual class (with convenient static methods) to define parallel task performance models.

Member Function Documentation

AMDAHL()

std::shared_ptr< ParallelModel > wrench::ParallelModel::AMDAHL ( double  alpha )

static

Create an instance of an "Amdahl" parallel model.

Parameters

alpha

the fraction (i.e., a number between 0.0 and 1.0) of the task's work that is perfectly parallelizable. Setting this value to 0 means that the task is purely sequential, and setting it to 1 means that the task is perfectly parallelizable.

Returns

a model instance

CONSTANTEFFICIENCY()

std::shared_ptr< ParallelModel > wrench::ParallelModel::CONSTANTEFFICIENCY ( double  efficiency )

static

Create an instance of a "Constant Efficiency" parallel model.

Parameters

efficiency

the parallel efficiency (which does not depend on the number of threads/cores).

Returns

a model instance

CUSTOM()

std::shared_ptr< ParallelModel > wrench::ParallelModel::CUSTOM ( std::function< std::vector< double >(double, long)>  lambda )

static

Create an instance of a "Custom" parallel model.

Parameters

lambda

a function that, when given a total flop amount and a number of threads, returns a vector of per-thread work amounts

Returns

a model instance

getWorkPerThread()

virtual std::vector<double> wrench::ParallelModel::getWorkPerThread ( double  total_work, unsigned long  num_threads  )

pure virtual

A method the, for this parallel model, computes how much work each thread that is part of a parallel task should do.

Parameters

total_work	the total amount of work (in flops)
num_threads	the number of threads

Returns

an amount of work (in flop) per thread

Implemented in wrench::AmdahlParallelModel, wrench::ConstantEfficiencyParallelModel, and wrench::CustomParallelModel.

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

• ParallelModel.h
• ParallelModel.cpp