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PsMultiThreadedPvmController Class Reference

a controller that uses a multi-threaded scheduler. More...

#include <PsMultiThreadedPvmController.h>

Inheritance diagram for PsMultiThreadedPvmController:

[legend]Collaboration diagram for PsMultiThreadedPvmController:

[legend]List of all members.

Public Methods
	PsMultiThreadedPvmController (PsObjectDescriptor &initialObjects, const PsDate &initialDate, int argc, char *argv[])
	constructor
virtual	~PsMultiThreadedPvmController ()
	destructor
virtual PsnScheduler *	createScheduler ()
	redefine to create a multihtreaded scheduler
virtual void	run ()
	redefine run to install a local memory manager
virtual PsSimulatedObject *	getPointerToSimulatedObjectNamed (const PsName &objectName)
	get a pointer to a simulation object.
virtual void	computeNextSimulationStep ()
	redefine to update the _pointerToObjectCache with the values of the _addToCache
Protected Attributes
unsigned int	_numberOfThreads
	the number of threads created
PsnMutexLock	_dataLock
	the lock to access _creatingObject and _creatingThread
PsnCondition	_accessCondition
	the boolean used to avoid recursive creation : should be accessed only protected
pthread_t	_accessingThread
	the thread id of the access lock
map< PsName, PsSimulatedObject * >	_pointerToObjectCache
	a cache that can be accessed lock free for getPointerToSimulatedObjectNamed
map< PsName, PsSimulatedObject * >	_addToCache
	a cache of objects that need to be added to the cache

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Detailed Description

a controller that uses a multi-threaded scheduler.

The number of threads used by this controller is controlled by the NumberOfThreads scheduling parameter.

• If this scheduling parameter is simple ( eg. NumberOfThreads 3), then all processes start the same number of threads.
• If this scheduling parameter is complex ( eg. NumberOfThreads { rvmax 6 onyx 4 Default 2 }), each process looks for the number of threads associated to it, or to the default number of thread if it hasn't been explicitely named. If no default value is given, the number of threads started is 2.

  Author:

  David Margery ( last change by )

  Version:

  1.1 ()

• 1.0 -> 1.1 by David Margery ( 2002/08/20): added support for different number of thread on each process

Definition at line 37 of file PsMultiThreadedPvmController.h.

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Constructor & Destructor Documentation

PsMultiThreadedPvmController::PsMultiThreadedPvmController (  PsObjectDescriptor &    initialObjects, const PsDate &    initialDate, int    argc, char *    argv[] )

constructor Parameters: numberOfThreads  the number of threads to create reads the number of threads from the NumberOfThreads scheduling parameter or defaults to 2 Definition at line 30 of file PsMultiThreadedPvmController.cxx. References _accessingThread, _numberOfThreads, PsConfigurationParameterDescriptor::getAssociatedString(), PsSimulatedObject::getObjectDescriptor(), PsObjectDescriptor::getSchedulingParameters(), PsMultipleConfigurationParameter::getSubDescriptorByName(), and PsDate. : PsPvmController(initialObjects, initialDate, argc, argv), _numberOfThreads (2), _accessingThread ( 0 ) { assert ( _accessingThread != pthread_self() ) ; if ( getObjectDescriptor().getSchedulingParameters() != NULL ) { const PsConfigurationParameterDescriptor * param = getObjectDescriptor().getSchedulingParameters()->getSubDescriptorByName("NumberOfThreads") ; if (param != NULL ) { // if the sheduling parameter named NumberOfThreads if a uniqueConfigurationParameter, then all processes should be spawned with the same number of threads, //otherwise read the number of threads from the appriate subdescriptor (the one with the name of the process, or default const PsMultipleConfigurationParameter * complexParam ; complexParam = dynamic_cast< const PsMultipleConfigurationParameter *> (param) ; if ( complexParam != NULL ) { // a multithreading value could by defined for each process //find the value for this process param = complexParam->getSubDescriptorByName (getObjectDescriptor().getProcess().getCString() ) ; if (param == NULL) { //no value has been defined for this process param = complexParam->getSubDescriptorByName ("default") ; if (param == NULL) {//no default value has been defined _numberOfThreads = 2 ; } else {// a default value has been defined _numberOfThreads = atoi (param->getAssociatedString().c_str() ) ; } } else {// a value has been defined for this process _numberOfThreads = atoi (param->getAssociatedString().c_str() ) ; } } else {// all processes use the same number of threads _numberOfThreads = atoi (param->getAssociatedString().c_str() ) ; } } } }

PsMultiThreadedPvmController::~PsMultiThreadedPvmController (    )  [virtual]

destructor Definition at line 86 of file PsMultiThreadedPvmController.cxx. { }

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Member Function Documentation

void PsMultiThreadedPvmController::computeNextSimulationStep (    )  [virtual]

redefine to update the _pointerToObjectCache with the values of the _addToCache Reimplemented from PsPvmController. Definition at line 180 of file PsMultiThreadedPvmController.cxx. References _addToCache, _pointerToObjectCache, map< PsName, PsSimulatedObject * >::begin(), map< PsName, PsSimulatedObject * >::clear(), PsPvmController::computeNextSimulationStep(), map< PsName, PsSimulatedObject * >::end(), and map< PsName, PsSimulatedObject * >::insert(). { _pointerToObjectCache.insert (_addToCache.begin() , _addToCache.end() ) ; _addToCache.clear() ; PsPvmController::computeNextSimulationStep () ; }

PsnScheduler * PsMultiThreadedPvmController::createScheduler (    )  [virtual]

redefine to create a multihtreaded scheduler Reimplemented from PsController. Definition at line 90 of file PsMultiThreadedPvmController.cxx. References PsController::_nbStepsByCycle, and _numberOfThreads. { return new PsnMultiThreadedScheduler( _nbStepsByCycle , _numberOfThreads, true ) ; }

PsSimulatedObject * PsMultiThreadedPvmController::getPointerToSimulatedObjectNamed (  const PsName &    objectName )  [virtual]

get a pointer to a simulation object. Redefined from PsPvmController, to protect sahred data structures Parameters: objectName  the name of the object for wich a pointer is needed Returns: a pointer to the corresponding object, non-const because thah pointer can be used to send events to the object Reimplemented from PsDistributedController. Definition at line 125 of file PsMultiThreadedPvmController.cxx. References _accessCondition, _accessingThread, _addToCache, _dataLock, _pointerToObjectCache, map< PsName, PsSimulatedObject * >::end(), map< PsName, PsSimulatedObject * >::find(), PsDistributedController::getPointerToSimulatedObjectNamed(), map< PsName, PsSimulatedObject * >::insert(), make_pair(), PsnMutexLock::protect(), PsnCondition::signalChange(), PsnMutexLock::unprotect(), and PsnCondition::waitForChange(). { PsSimulatedObject * result ; map<PsName, PsSimulatedObject * >::iterator i = _pointerToObjectCache.find ( objectName ) ; if ( i != _pointerToObjectCache.end() ) { result = i->second ; } else { _dataLock.protect() ; i = _addToCache.find (objectName) ; if ( i != _addToCache.end() ) { result = i->second ; _dataLock.unprotect() ; } else { if ( _accessingThread == pthread_self() ) { _dataLock.unprotect() ; result = PsPvmController::getPointerToSimulatedObjectNamed ( objectName ) ; } else if ( _accessingThread == 0 ) { _accessingThread = pthread_self() ; _dataLock.unprotect() ; result = PsPvmController::getPointerToSimulatedObjectNamed ( objectName ) ; _dataLock.protect() ; _accessingThread = 0 ; _dataLock.unprotect() ; _accessCondition.signalChange() ; } else { //other thread is accessing: wait _accessCondition.waitForChange ( _dataLock ) ; _dataLock.unprotect() ; result = getPointerToSimulatedObjectNamed ( objectName ) ; } _dataLock.protect() ; _addToCache.insert ( make_pair(objectName,result) ) ; _dataLock.unprotect() ; } } return result ; }

void PsMultiThreadedPvmController::run (    )  [virtual]

redefine run to install a local memory manager Reimplemented from PsPvmController. Definition at line 95 of file PsMultiThreadedPvmController.cxx. References HeapStackTop::getSystemMemoryManager(), and PsPvmController::run(). { PsnMemoryManager * currentMemoryManager = HeapStackTop::getSystemMemoryManager() ; assert ( currentMemoryManager != 0 ) ; // commented out because a thread memory manager doesn't seem performant : confirmed : our implementation performs very poorly compared to the malloc implementation on the demarshalling phase //size_t initialAllocatatedMemory = 1024 * 1024 ; //void * startMemory = currentMemoryManager->allocateSizeRemembered ( initialAllocatatedMemory ) ; //PsnDescriptorMemoryManager * descriptorMemoryManager = new PsnDescriptorMemoryManager ( *currentMemoryManager ) ; //descriptorMemoryManager->init() ; //PsnThreadMemoryManager * memoryManagerForThisThread ; //memoryManagerForThisThread = new PsnThreadMemoryManager ( startMemory, // initialAllocatatedMemory, // *currentMemoryManager, // *descriptorMemoryManager ) ; //memoryManagerForThisThread -> init() ; //HeapStackTop allocationContextForThisThread ( memoryManagerForThisThread ) ; PsPvmController::run() ; }

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Member Data Documentation

PsnCondition PsMultiThreadedPvmController::_accessCondition [mutable, protected]

the boolean used to avoid recursive creation : should be accessed only protected Definition at line 75 of file PsMultiThreadedPvmController.h. Referenced by getPointerToSimulatedObjectNamed().

pthread_t PsMultiThreadedPvmController::_accessingThread [mutable, protected]

the thread id of the access lock Definition at line 78 of file PsMultiThreadedPvmController.h. Referenced by getPointerToSimulatedObjectNamed(), and PsMultiThreadedPvmController().

map<PsName, PsSimulatedObject * > PsMultiThreadedPvmController::_addToCache [protected]

a cache of objects that need to be added to the cache Definition at line 84 of file PsMultiThreadedPvmController.h. Referenced by computeNextSimulationStep(), and getPointerToSimulatedObjectNamed().

PsnMutexLock PsMultiThreadedPvmController::_dataLock [mutable, protected]

the lock to access _creatingObject and _creatingThread Definition at line 72 of file PsMultiThreadedPvmController.h. Referenced by getPointerToSimulatedObjectNamed().

unsigned int PsMultiThreadedPvmController::_numberOfThreads [protected]

the number of threads created Definition at line 69 of file PsMultiThreadedPvmController.h. Referenced by createScheduler(), and PsMultiThreadedPvmController().

map<PsName, PsSimulatedObject * > PsMultiThreadedPvmController::_pointerToObjectCache [protected]

a cache that can be accessed lock free for getPointerToSimulatedObjectNamed Definition at line 81 of file PsMultiThreadedPvmController.h. Referenced by computeNextSimulationStep(), and getPointerToSimulatedObjectNamed().

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

• PsMultiThreadedPvmController.h
• PsMultiThreadedPvmController.cxx

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