MySQL wrapper for a condition variable, template which may be specialized with a specific implementation of a condition variable, e.g. More...

#include <thread_pool.h>

Public Types
using	Thread = concurrency::Thread
	Thread type. More...

using	Task_type = std::packaged_task< T(unsigned int)>
	Runnable task type, future is obtained by the caller. More...

using	Queue_type = concurrency::Sync_bounded_queue< Task_type, t_queue_size >
	Queue type used to synchronize a thread supplying task to this thread pool and worker threads. More...

using	St_key = mysql::concurrency::Stage_key

using	Th_key = mysql::concurrency::Thread_key

using	Thread_allocator = mysql::allocators::Allocator< Thread >

Public Member Functions
	Thread_pool (unsigned int thread_num=std::thread::hardware_concurrency(), unsigned int instance_id=0, Thread_pool_psi psi_params={})
	Constructs a thread pool. More...

bool	init ()
	Initializes the thread pool by starting worker threads. More...

void	deinit ()
	Deinitializes the thread pool and joins all worker threads. More...

void	enqueue (Task_type &&task)
	Enqueues task for execution. More...

virtual	~Thread_pool ()
	Destructor. More...

void	end_execution ()
	Notifies all threads to end execution in a gracious way. More...

	Thread_pool (Thread_pool &&) noexcept=delete

Thread_pool &	operator= (Thread_pool &&) noexcept=delete

	Thread_pool (const Thread_pool &)=delete

Thread_pool &	operator= (const Thread_pool &)=delete

std::string	print_queue_state () const
	Prints worker queue state, debug function. More...

std::size_t	queue_size () const
	Get an estimation of number of elements in the worker queue. More...

std::size_t	size () const
	Obtains worker pool size. More...

Private Member Functions
void	run_worker (unsigned int thread_id)
	Function executed by each thread. More...

Static Private Member Functions
static bool	has_creation_error (const Thread &thread)
	Checks whether worker thread construction failed. More...

Private Attributes
std::vector< Thread, Thread_allocator >	m_workers
	Thread container. More...

std::unordered_map< unsigned int, std::atomic< bool > >	m_end_execution
	Variable indicating the end of execution, allows threads to stop in a gracious way. More...

Queue_type	m_tasks
	Enqueued, ready to be executed tasks. More...

unsigned int	m_workers_num
	The number of threads in the thread pool. More...

unsigned int	m_instance_id {0}
	Instance id. More...

Thread_pool_psi	m_psi
	PSI parameters. More...

bool	m_initialized {false}
	Whether init() completed successfully. More...

Detailed Description

template<class T, std::size_t t_queue_size = 8192>
class mysql::scheduler::Thread_pool< T, t_queue_size >

MySQL wrapper for a condition variable, template which may be specialized with a specific implementation of a condition variable, e.g.

MySQL condition variable, and satisfying the following requirements:

Member Typedef Documentation

◆ Queue_type

template<class T , std::size_t t_queue_size = 8192>

using mysql::scheduler::Thread_pool< T, t_queue_size >::Queue_type = concurrency::Sync_bounded_queue<Task_type, t_queue_size>

Queue type used to synchronize a thread supplying task to this thread pool and worker threads.

Worker threads are consumers of this queue type

◆ St_key

template<class T , std::size_t t_queue_size = 8192>

using mysql::scheduler::Thread_pool< T, t_queue_size >::St_key = mysql::concurrency::Stage_key

◆ Task_type

template<class T , std::size_t t_queue_size = 8192>

using mysql::scheduler::Thread_pool< T, t_queue_size >::Task_type = std::packaged_task<T(unsigned int)>

Runnable task type, future is obtained by the caller.

◆ Th_key

template<class T , std::size_t t_queue_size = 8192>

using mysql::scheduler::Thread_pool< T, t_queue_size >::Th_key = mysql::concurrency::Thread_key

◆ Thread

template<class T , std::size_t t_queue_size = 8192>

using mysql::scheduler::Thread_pool< T, t_queue_size >::Thread = concurrency::Thread

Thread type.

◆ Thread_allocator

template<class T , std::size_t t_queue_size = 8192>

using mysql::scheduler::Thread_pool< T, t_queue_size >::Thread_allocator = mysql::allocators::Allocator<Thread>

Constructor & Destructor Documentation

◆ Thread_pool() [1/3]

template<class T , std::size_t t_queue_size>

mysql::scheduler::Thread_pool< T, t_queue_size >::Thread_pool	(	unsigned int	thread_num = `std::thread::hardware_concurrency()`,
		unsigned int	instance_id = `0`,
		Thread_pool_psi	psi_params = `{}`
	)

Constructs a thread pool.

Parameters

thread_num	Numbers of threads in a thread pool, set as default to the number of concurrent threads supported by the implementation
instance_id	THP will gather statistics for this instance id
psi_params	PSI parameters

◆ ~Thread_pool()

template<class T , std::size_t t_queue_size>

mysql::scheduler::Thread_pool< T, t_queue_size >::~Thread_pool

virtual

Destructor.

◆ Thread_pool() [2/3]

template<class T , std::size_t t_queue_size = 8192>

mysql::scheduler::Thread_pool< T, t_queue_size >::Thread_pool ( Thread_pool< T, t_queue_size > && )

deletenoexcept

◆ Thread_pool() [3/3]

template<class T , std::size_t t_queue_size = 8192>

mysql::scheduler::Thread_pool< T, t_queue_size >::Thread_pool ( const Thread_pool< T, t_queue_size > & )

delete

Member Function Documentation

◆ deinit()

template<class T , std::size_t t_queue_size>

void mysql::scheduler::Thread_pool< T, t_queue_size >::deinit

Deinitializes the thread pool and joins all worker threads.

◆ end_execution()

template<class T , std::size_t t_queue_size>

void mysql::scheduler::Thread_pool< T, t_queue_size >::end_execution

Notifies all threads to end execution in a gracious way.

When finished, Thread_pool object is ready to be destroyed. This function is called in destructor.

◆ enqueue()

template<class T , std::size_t t_queue_size>

void mysql::scheduler::Thread_pool< T, t_queue_size >::enqueue ( Task_type && task )

Enqueues task for execution.

Parameters

task	Functor to be executed by the thread pool

◆ has_creation_error()

template<class T , std::size_t t_queue_size>

bool mysql::scheduler::Thread_pool< T, t_queue_size >::has_creation_error ( const Thread & thread )

staticprivate

Checks whether worker thread construction failed.

Parameters

thread Worker thread object.

Returns: True on failure, false otherwise.

◆ init()

template<class T , std::size_t t_queue_size>

bool mysql::scheduler::Thread_pool< T, t_queue_size >::init

Initializes the thread pool by starting worker threads.

Return values

false	Success
true	Failure

◆ operator=() [1/2]

template<class T , std::size_t t_queue_size = 8192>

Thread_pool & mysql::scheduler::Thread_pool< T, t_queue_size >::operator= ( const Thread_pool< T, t_queue_size > & )

delete

◆ operator=() [2/2]

template<class T , std::size_t t_queue_size = 8192>

Thread_pool & mysql::scheduler::Thread_pool< T, t_queue_size >::operator= ( Thread_pool< T, t_queue_size > && )

deletenoexcept

◆ print_queue_state()

template<class T , std::size_t t_queue_size>

std::string mysql::scheduler::Thread_pool< T, t_queue_size >::print_queue_state

Prints worker queue state, debug function.

Returns: String with internal queue state

◆ queue_size()

template<class T , std::size_t t_queue_size>

std::size_t mysql::scheduler::Thread_pool< T, t_queue_size >::queue_size

Get an estimation of number of elements in the worker queue.

Returns: The number of elements in the worker queue

◆ run_worker()

template<class T , std::size_t t_queue_size>

void mysql::scheduler::Thread_pool< T, t_queue_size >::run_worker ( unsigned int thread_id )

private

Function executed by each thread.

◆ size()

template<class T , std::size_t t_queue_size>

std::size_t mysql::scheduler::Thread_pool< T, t_queue_size >::size

Obtains worker pool size.

Returns: The number of workers available in the pool

Member Data Documentation

◆ m_end_execution

template<class T , std::size_t t_queue_size = 8192>

std::unordered_map<unsigned int, std::atomic<bool> > mysql::scheduler::Thread_pool< T, t_queue_size >::m_end_execution

private

Variable indicating the end of execution, allows threads to stop in a gracious way.

◆ m_initialized

template<class T , std::size_t t_queue_size = 8192>

bool mysql::scheduler::Thread_pool< T, t_queue_size >::m_initialized {false}

private

Whether init() completed successfully.

◆ m_instance_id

template<class T , std::size_t t_queue_size = 8192>

unsigned int mysql::scheduler::Thread_pool< T, t_queue_size >::m_instance_id {0}

private

Instance id.

◆ m_psi

template<class T , std::size_t t_queue_size = 8192>

Thread_pool_psi mysql::scheduler::Thread_pool< T, t_queue_size >::m_psi

private

PSI parameters.

◆ m_tasks

template<class T , std::size_t t_queue_size = 8192>

Queue_type mysql::scheduler::Thread_pool< T, t_queue_size >::m_tasks

private

Enqueued, ready to be executed tasks.

◆ m_workers

template<class T , std::size_t t_queue_size = 8192>

std::vector<Thread, Thread_allocator> mysql::scheduler::Thread_pool< T, t_queue_size >::m_workers

private

Thread container.

◆ m_workers_num

template<class T , std::size_t t_queue_size = 8192>

unsigned int mysql::scheduler::Thread_pool< T, t_queue_size >::m_workers_num

private

The number of threads in the thread pool.

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

libs/mysql/scheduler/thread_pool.h
libs/mysql/scheduler/thread_pool_impl.hpp

Public Types

Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ Queue_type

◆ St_key

◆ Task_type

◆ Th_key

◆ Thread

◆ Thread_allocator

Constructor & Destructor Documentation

◆ Thread_pool() [1/3]

◆ ~Thread_pool()

◆ Thread_pool() [2/3]

◆ Thread_pool() [3/3]

Member Function Documentation

◆ deinit()

◆ end_execution()

◆ enqueue()

◆ has_creation_error()

◆ init()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ print_queue_state()

◆ queue_size()

◆ run_worker()

◆ size()

Member Data Documentation

◆ m_end_execution

◆ m_initialized

◆ m_instance_id

◆ m_psi

◆ m_tasks

◆ m_workers

◆ m_workers_num