A singleton pool of threads for dynamic execution of tasks. More...

#include <thread.h>

Collaboration diagram for madness::ThreadPool:

[legend]

Public Member Functions
	ThreadPool (const ThreadPool &)=delete

	ThreadPool (ThreadPool &&)=delete

	~ThreadPool ()
	Destructor.

void	flush_prebuf ()

void	operator= (const ThreadPool &)=delete

void	operator= (ThreadPool &&)=delete

template<typename opT >
void	scan (opT &op)

Static Public Member Functions
static void	add (const std::vector< PoolTaskInterface * > &tasks)
	Add a vector of tasks to the pool.

static void	add (PoolTaskInterface *task)
	Add a new task to the pool.

template<typename Probe >
static void	await (const Probe &probe, bool dowork=true, bool sleep=false)
	Gracefully wait for a condition to become true, executing any tasks in the queue.

static void	begin (int nthread=-1)
	Please invoke while in a single-threaded environment.

static int	default_nthread ()
	Get the number of threads from the environment.

static void	end ()

static const DQStats &	get_stats ()
	Returns queue statistics.

static const ThreadPoolThread *	get_threads ()

static ThreadPool *	instance ()
	Return a pointer to the only instance, constructing as necessary.

static std::size_t	queue_size ()
	Returns the number of tasks in the queue.

static bool	run_task ()
	An otherwise idle thread can all this to run a task.

static void	set_wait_policy (WaitPolicy policy, int sleep_duration_in_microseconds=0)

static std::size_t	size ()
	Returns the number of threads in the pool.

Static Public Attributes
static std::unique_ptr< tbb::task_arena >	tbb_arena = nullptr

static std::unique_ptr< tbb::global_control >	tbb_control = nullptr

Private Member Functions
	ThreadPool (int nthread=-1)
	The constructor is private to enforce the singleton model.

bool	run_task (bool wait, ThreadPoolThread *this_thread)
	Run the next task.

bool	run_tasks (bool wait, ThreadPoolThread *const this_thread)

void	thread_main (ThreadPoolThread *const thread)

Static Private Member Functions
static void *	pool_thread_main (void *v)
	Forwards the thread to bound member function.

Private Attributes
volatile bool	finish
	Set to true when time to stop.

ThreadPoolThread	main_thread
	Placeholder for main thread tls.

AtomicInt	nfinished
	Thread pool exit counter.

int	nthreads
	Number of threads.

DQueue< PoolTaskInterface * >	queue
	Queue of tasks.

ThreadPoolThread *	threads
	Array of threads.

Static Private Attributes
static double	await_timeout = 900.0
	Waiter timeout.

static ThreadPool *	instance_ptr = 0
	Singleton pointer.

static const int	nmax = 128
	Number of task a worker thread will pop from the task queue.

Friends
class	WorldTaskQueue

Detailed Description

A singleton pool of threads for dynamic execution of tasks.

Attention: You must instantiate the pool while running with just one thread.

Constructor & Destructor Documentation

◆ ThreadPool() [1/3]

madness::ThreadPool::ThreadPool ( const ThreadPool & )

delete

◆ ThreadPool() [2/3]

madness::ThreadPool::ThreadPool ( ThreadPool && )

delete

◆ ThreadPool() [3/3]

madness::ThreadPool::ThreadPool ( int nthread = -1 )

private

The constructor is private to enforce the singleton model.

Todo:: Description needed.

Parameters

[in] nthread Description needed.

References SafeMPI::COMM_WORLD, default_nthread(), SafeMPI::Intracomm::Get_size(), instance_ptr, MADNESS_ASSERT, MADNESS_EXCEPTION, main_thread, nfinished, nthreads, pool_thread_main(), madness::ThreadBase::set_pool_thread_index(), madness::Thread::start(), tbb_arena, tbb_control, madness::ThreadBase::thread_key, and threads.

◆ ~ThreadPool()

madness::ThreadPool::~ThreadPool ( )

inline

Destructor.

References threads.

Member Function Documentation

◆ add() [1/2]

static void madness::ThreadPool::add ( const std::vector< PoolTaskInterface * > & tasks )

inlinestatic

Add a vector of tasks to the pool.

Parameters

[in] tasks Vector of tasks to add to the pool.

References add(), and MADNESS_EXCEPTION.

◆ add() [2/2]

static void madness::ThreadPool::add ( PoolTaskInterface * task )

inlinestatic

Add a new task to the pool.

Todo:: Description needed.

Parameters

[in,out] task Description needed.

References instance(), MADNESS_EXCEPTION, queue, task(), and tbb_arena.

Referenced by add(), end(), main(), and madness::TaskInterface::Submit::notify().

◆ await()

template<typename Probe >

static void madness::ThreadPool::await	(	const Probe &	probe,
		bool	dowork = `true`,
		bool	sleep = `false`
	)

inlinestatic

Gracefully wait for a condition to become true, executing any tasks in the queue.

Probe should be an object that, when called, returns the status.

Todo:: Descriptions needed/need verification.

Template Parameters

Probe Type of the probe.

Parameters

[in]	probe	The probe.
[in]	dowork	Do work while waiting - default is true
[in]	sleep	Sleep instead of spin while waiting (e.g., to avoid pounding on MPI) - default is false

References await_timeout, bufsize, madness::cpu_time(), current_time, madness::myusleep(), madness::MutexWaiter::reset(), run_task(), and madness::MutexWaiter::wait().

Referenced by madness::World::await(), madness::World::await(), and madness::WorldTaskQueue::fence().

◆ begin()

void madness::ThreadPool::begin ( int nthread = -1 )

static

Please invoke while in a single-threaded environment.

Todo:: Verify documentation.

Parameters

[in] nthread The number of threads.

References await_timeout, SafeMPI::COMM_WORLD, SafeMPI::Intracomm::Get_rank(), madness::ThreadBase::init_thread_key(), instance_ptr, madness::profiling::TaskProfiler::output_file_name_, madness::quiet(), and size().

◆ default_nthread()

int madness::ThreadPool::default_nthread ( )

static

Get the number of threads from the environment.

Returns: The number of threads.

References MADNESS_EXCEPTION, madness::ThreadBase::num_hw_processors(), and shift.

Referenced by ThreadPool().

◆ end()

void madness::ThreadPool::end ( )

static

Todo:: Description needed.

References add(), madness::ThreadBase::delete_thread_key(), finish, flush_prebuf(), instance(), instance_ptr, main_thread, nfinished, nthreads, madness::ThreadPoolThread::profiler(), and madness::profiling::TaskProfiler::write_to_file().

◆ flush_prebuf()

void madness::ThreadPool::flush_prebuf ( )

inline

References queue.

Referenced by end(), and madness::RMI::RmiTask::process_some().

◆ get_stats()

const DQStats & madness::ThreadPool::get_stats ( )

static

Returns queue statistics.

Returns: Queue statistics.

References instance(), and queue.

Referenced by madness::print_stats().

◆ get_threads()

static const ThreadPoolThread * madness::ThreadPool::get_threads ( )

inlinestatic

Access the pool thread array

Returns: ptr to the pool thread array, its size is given by size()

References instance(), and threads.

◆ instance()

static ThreadPool * madness::ThreadPool::instance ( )

inlinestatic

Return a pointer to the only instance, constructing as necessary.

Returns: A pointer to the only instance.

References instance_ptr, and MADNESS_EXCEPTION.

Referenced by add(), end(), get_stats(), get_threads(), pool_thread_main(), madness::RMI::RmiTask::process_some(), queue_size(), run_task(), set_wait_policy(), and size().

◆ operator=() [1/2]

void madness::ThreadPool::operator= ( const ThreadPool & )

delete

◆ operator=() [2/2]

void madness::ThreadPool::operator= ( ThreadPool && )

delete

◆ pool_thread_main()

void * madness::ThreadPool::pool_thread_main ( void * v )

staticprivate

Forwards the thread to bound member function.

Todo:: Descriptions needed.

Parameters

[in] v Description needed.

Returns: Description needed.

References instance(), thread_main(), and v.

Referenced by ThreadPool().

◆ queue_size()

static std::size_t madness::ThreadPool::queue_size ( )

inlinestatic

Returns the number of tasks in the queue.

Returns: The number of tasks in the queue.

References instance(), and queue.

◆ run_task() [1/2]

static bool madness::ThreadPool::run_task ( )

inlinestatic

An otherwise idle thread can all this to run a task.

Returns: True if a task was run.

References instance(), run_tasks(), and madness::ThreadBase::this_thread().

Referenced by await(), and thread_main().

◆ run_task() [2/2]

bool madness::ThreadPool::run_task	(	bool	wait,
		ThreadPoolThread *	this_thread
	)

inlineprivate

Run the next task.

Todo:: Verify and complete this documentation.

Parameters

[in]	wait	Block of true.
[in,out]	this_thread	Description needed.

Returns: True if a task was run.

References madness::profiling::TaskEventList::event(), MADNESS_EXCEPTION, madness::profiling::TaskProfiler::new_list(), madness::ThreadPoolThread::profiler(), and queue.

◆ run_tasks()

bool madness::ThreadPool::run_tasks	(	bool	wait,
		ThreadPoolThread *const	this_thread
	)

inlineprivate

Todo:: Brief description needed.

Todo:: Descriptions needed.

Parameters

[in]	wait	Description needed.
[in,out]	this_thread	Description needed.

Returns: Description needed.

References madness::profiling::TaskEventList::event(), MADNESS_EXCEPTION, madness::profiling::TaskProfiler::new_list(), nmax, madness::ThreadPoolThread::profiler(), queue, and madness::PoolTaskInterface::set_event().

Referenced by run_task(), and thread_main().

◆ scan()

template<typename opT >

void madness::ThreadPool::scan ( opT & op )

inline

Todo:: Brief description needed.

Todo:: Descriptions needed.

Template Parameters

opT	Description needed.

Parameters

[in,out] op Description needed.

References op(), and queue.

◆ set_wait_policy()

static void madness::ThreadPool::set_wait_policy	(	WaitPolicy	policy,
		int	sleep_duration_in_microseconds = `0`
	)

inlinestatic

See also: madness::threadpool_wait_policy

References instance(), and queue.

Referenced by madness::threadpool_wait_policy().

◆ size()

static std::size_t madness::ThreadPool::size ( )

inlinestatic

Returns the number of threads in the pool.

Returns: The number of threads in the pool.

References instance(), and nthreads.

Referenced by madness::CubicInterpolationTable< T >::CubicInterpolationTable(), begin(), madness::RMI::RmiTask::huge_msg_handler(), main(), madness::print_stats(), madness::archive::ArchiveStoreImpl< ParallelOutputArchive< VectorOutputArchive >, WorldContainer< keyT, valueT > >::store(), test2(), test_multi(), and madness::profiling::TaskProfiler::write_to_file().

◆ thread_main()

void madness::ThreadPool::thread_main ( ThreadPoolThread *const thread )

private

Todo:: Brief description needed.

Todo:: Description needed.

Parameters

[in,out] thread Description needed.

References madness::ThreadBinder::bind(), madness::binder, finish, nfinished, PROFILE_MEMBER_FUNC, madness::ThreadPoolThread::profiler(), run_task(), run_tasks(), and madness::profiling::TaskProfiler::write_to_file().

Referenced by pool_thread_main().

Friends And Related Symbol Documentation

◆ WorldTaskQueue

friend class WorldTaskQueue

friend

Member Data Documentation

◆ await_timeout

double madness::ThreadPool::await_timeout = 900.0

staticprivate

Waiter timeout.

Referenced by await(), and begin().

◆ finish

volatile bool madness::ThreadPool::finish

private

Set to true when time to stop.

Referenced by end(), and thread_main().

◆ instance_ptr

ThreadPool * madness::ThreadPool::instance_ptr = 0

staticprivate

Singleton pointer.

Referenced by ThreadPool(), begin(), end(), and instance().

◆ main_thread

ThreadPoolThread madness::ThreadPool::main_thread

private

Placeholder for main thread tls.

Referenced by ThreadPool(), and end().

◆ nfinished

AtomicInt madness::ThreadPool::nfinished

private

Thread pool exit counter.

Referenced by ThreadPool(), end(), and thread_main().

◆ nmax

const int madness::ThreadPool::nmax = 128

staticprivate

Number of task a worker thread will pop from the task queue.

Referenced by run_tasks().

◆ nthreads

int madness::ThreadPool::nthreads

private

Number of threads.

Referenced by ThreadPool(), end(), and size().

◆ queue

DQueue<PoolTaskInterface*> madness::ThreadPool::queue

private

Queue of tasks.

Referenced by add(), flush_prebuf(), get_stats(), queue_size(), run_task(), run_tasks(), scan(), and set_wait_policy().

◆ tbb_arena

std::unique_ptr< tbb::task_arena > madness::ThreadPool::tbb_arena = nullptr

static

Referenced by ThreadPool(), add(), and madness::RMI::begin().

◆ tbb_control

std::unique_ptr< tbb::global_control > madness::ThreadPool::tbb_control = nullptr

static

Todo:: Description needed.

Referenced by ThreadPool().

◆ threads

ThreadPoolThread* madness::ThreadPool::threads

private

Array of threads.

Referenced by ThreadPool(), ~ThreadPool(), and get_threads().

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

Public Member Functions

Static Public Member Functions

Static Public Attributes

Private Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ ThreadPool() [1/3]

◆ ThreadPool() [2/3]

◆ ThreadPool() [3/3]

◆ ~ThreadPool()

Member Function Documentation

◆ add() [1/2]

◆ add() [2/2]

◆ await()

◆ begin()

◆ default_nthread()

◆ end()

◆ flush_prebuf()

◆ get_stats()

◆ get_threads()

◆ instance()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ pool_thread_main()

◆ queue_size()

◆ run_task() [1/2]

◆ run_task() [2/2]

◆ run_tasks()

◆ scan()

◆ set_wait_policy()

◆ size()

◆ thread_main()

Friends And Related Symbol Documentation

◆ WorldTaskQueue

Member Data Documentation

◆ await_timeout

◆ finish

◆ instance_ptr

◆ main_thread

◆ nfinished

◆ nmax

◆ nthreads

◆ queue

◆ tbb_arena

◆ tbb_control

◆ threads