Description:

The set of management parameters that determine how a thread pool balances the number of worker threads.

Definition at line 72 of file threadpool.inl.

Public Type Index:
enum class	Modes { Fixed , Auto }
	The modes, fixed or automatic. More...

Public Field Index:
Ticks::Duration	DecreaseSchedule = Ticks::Duration::FromAbsoluteMilliseconds(500)

int	DecreaseThreshold = 70

int	FixedSize = ThreadPool::HardwareConcurrency()

Ticks::Duration	IncreaseSchedule = Ticks::Duration::FromAbsoluteMilliseconds(0)

int	IncreaseThreshold = 300

Modes	Mode =Modes::Auto
	The mode of operation.

int	WorkersMax = ThreadPool::HardwareConcurrency()
	The maximum number of threads to create.

int	WorkersMin = 0
	The minimum number of threads to keep alive.

Protected Method Index:
int	GetSize (int currentWorkers, int idleWorkers, int load, Ticks &lastChangeTime)

Friends And Related Entity Details:

◆ ThreadPool

friend class ThreadPool

friend

Type alias in namespace alib.

Definition at line 74 of file threadpool.inl.

Enumeration Details:

◆ Modes

enum class alib::threadmodel::ThreadPool::ResizeStrategy::Modes

strong

The modes, fixed or automatic.

Enumerator
Fixed	The number of threads is fixed.
Auto	The number of threads is increased when the load increases and decreased when the load decreases.

Definition at line 77 of file threadpool.inl.

Field Details:

◆ DecreaseSchedule

Ticks::Duration alib::threadmodel::ThreadPool::ResizeStrategy::DecreaseSchedule = Ticks::Duration::FromAbsoluteMilliseconds(500)

The duration of that the pool has to be underloaded before a decrease of threads starts. Defaults to 500ms.

Definition at line 121 of file threadpool.inl.

◆ DecreaseThreshold

int alib::threadmodel::ThreadPool::ResizeStrategy::DecreaseThreshold = 70

A threshold in percent that determines at which underload factor the number of threads are decreased. Defaults to 50%. For example, 30% this means that if 70% of the threads are idle the number of threads is decreased.

Definition at line 112 of file threadpool.inl.

◆ FixedSize

int alib::threadmodel::ThreadPool::ResizeStrategy::FixedSize = ThreadPool::HardwareConcurrency()

The number of threads to create (or decrease to). If Mode equals Fixed, this is used and all other parameters are ignored. If Mode equals Auto, this field is ignored and the other parameters are used.

Definition at line 93 of file threadpool.inl.

◆ IncreaseSchedule

Ticks::Duration alib::threadmodel::ThreadPool::ResizeStrategy::IncreaseSchedule = Ticks::Duration::FromAbsoluteMilliseconds(0)

The duration of that the pool has to be overloaded before an increase of threads starts. Defaults to zero time interval.

Definition at line 117 of file threadpool.inl.

◆ IncreaseThreshold

int alib::threadmodel::ThreadPool::ResizeStrategy::IncreaseThreshold = 300

A threshold in percent that determines at which overload factor the number of threads are increased. Defaults to 300%. For example, this means if the pool currently holds 10 threads, then new threads are created when the load increases to 30 unprocess jobs.

Definition at line 105 of file threadpool.inl.

◆ Mode

Modes alib::threadmodel::ThreadPool::ResizeStrategy::Mode =Modes::Auto

The mode of operation.

Definition at line 88 of file threadpool.inl.

◆ WorkersMax

int alib::threadmodel::ThreadPool::ResizeStrategy::WorkersMax = ThreadPool::HardwareConcurrency()

The maximum number of threads to create.

Definition at line 96 of file threadpool.inl.

◆ WorkersMin

int alib::threadmodel::ThreadPool::ResizeStrategy::WorkersMin = 0

The minimum number of threads to keep alive.

Definition at line 99 of file threadpool.inl.

Method Details:

◆ GetSize()

int alib::threadmodel::ThreadPool::ResizeStrategy::GetSize	(	int	currentWorkers,
		int	idleWorkers,
		int	load,
		Ticks &	lastChangeTime )

inlineprotected

Calculates the target size, depending on the parameters set in this struct and the actual values passed.

Parameters

currentWorkers	The number of threads currently in the pool.
idleWorkers	The size of the subset of threads currently idle.
load	The number of jobs currently queued.
lastChangeTime	Time point of last increase or decrease.

Returns: The new target size.

Definition at line 133 of file threadpool.inl.

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

threadpool.inl