BaseLib::IQueue Class Reference

This class implements a queue after the producer-consumer paradigm. More...

#include <IQueue.h>

Inheritance diagram for BaseLib::IQueue:

Public Member Functions
	IQueue (SharedObjects *baseLib, uint32_t queueCount, uint32_t bufferSize)
	Constructor. More...
virtual	~IQueue ()
void	startQueue (int32_t index, bool waitWhenFull, uint32_t processingThreadCount, int32_t threadPriority=0, int32_t threadPolicy=SCHED_OTHER)
	Starts the threads of a queue. More...
void	startQueue (int32_t index, bool waitWhenFull, uint32_t initialProcessingThreadCount, uint32_t maxProcessingThreadCount)
	Starts the threads of a queue using a thread count that can be increased later. More...
void	stopQueue (int32_t index)
	Stops the threads of a queue previously started with startQueue(). More...
bool	queueIsStarted (int32_t index)
	Checks if the specified queue has been started. More...
bool	addThread (int32_t index)
	Start an additional thread. More...
bool	enqueue (int32_t index, std::shared_ptr< IQueueEntry > &entry, bool waitWhenFull=false)
	Enqueues an item. More...
virtual void	processQueueEntry (int32_t index, std::shared_ptr< IQueueEntry > &entry)=0
	This method is called by the processing threads for each item to process. More...
bool	queueEmpty (int32_t index)
	Checks if a queue is empty. More...
uint32_t	processingThreadCount (int32_t index)
	Returns the number of processing threads. More...
uint32_t	maxProcessingThreadCount (int32_t index)
	Returns the maximum number of processing threads. More...
int32_t	queueSize (int32_t index)
	Returns the number of items queued in a queue. More...
double	threadLoad (int32_t index)
double	maxThreadLoad (int32_t index)
double	maxThreadLoad1m (int32_t index)
double	maxThreadLoad10m (int32_t index)
double	maxThreadLoad1h (int32_t index)
int64_t	maxWait (int32_t index)
int64_t	maxWait1m (int32_t index)
int64_t	maxWait10m (int32_t index)
int64_t	maxWait1h (int32_t index)
Public Member Functions inherited from BaseLib::IQueueBase
	IQueueBase (SharedObjects *baseLib, uint32_t queueCount)
virtual	~IQueueBase ()
void	printQueueFullError (BaseLib::Output &out, const std::string &message)
	Prints a rate limited (1 output per 10 seconds) error message and keeps count of error messages. More...

Additional Inherited Members
Protected Attributes inherited from BaseLib::IQueueBase
SharedObjects *	_bl = nullptr
int32_t	_queueCount = 2
std::unique_ptr< std::atomic_bool[]>	_stopProcessingThread
std::atomic< uint32_t >	_droppedEntries {0}
std::atomic< int64_t >	_lastQueueFullError {0}

Detailed Description

This class implements a queue after the producer-consumer paradigm.

It can manage one or more queues. Your class needs to be derived from IQueue to use it.

Constructor & Destructor Documentation

IQueue()

BaseLib::IQueue::IQueue	(	SharedObjects *	baseLib,
		uint32_t	queueCount,
		uint32_t	bufferSize
	)

Constructor.

Parameters

baseLib	A base library object.
queueCount	The number of queues to initialize.
bufferSize	The maximum number of items allowed to be queued.

~IQueue()

BaseLib::IQueue::~IQueue ( )

virtual

Member Function Documentation

addThread()

bool BaseLib::IQueue::addThread

(

int32_t

index

)

Start an additional thread.

Parameters

index

The index of the queue to add the new thread.

Returns

Returns true when the thread could be started.

enqueue()

bool BaseLib::IQueue::enqueue	(	int32_t	index,
		std::shared_ptr< IQueueEntry > &	entry,
		bool	waitWhenFull = false
	)

Enqueues an item.

Parameters

index	The index of the queue to enqueue the item into.
entry	The item to queue.
waitWhenFull	When set to true the method waits until the queue is empty enough to queue the item. When waitWhenFull is set to true in startQueue(), this argument is ignored.

Returns

Returns true if the item was successfully queued and false otherwise.

maxProcessingThreadCount()

uint32_t BaseLib::IQueue::maxProcessingThreadCount

(

int32_t

index

)

Returns the maximum number of processing threads.

Returns

The number maximum number of processing threads for this queue.

maxThreadLoad()

double BaseLib::IQueue::maxThreadLoad

(

int32_t

index

)

maxThreadLoad10m()

double BaseLib::IQueue::maxThreadLoad10m

(

int32_t

index

)

maxThreadLoad1h()

double BaseLib::IQueue::maxThreadLoad1h

(

int32_t

index

)

maxThreadLoad1m()

double BaseLib::IQueue::maxThreadLoad1m

(

int32_t

index

)

maxWait()

int64_t BaseLib::IQueue::maxWait

(

int32_t

index

)

maxWait10m()

int64_t BaseLib::IQueue::maxWait10m

(

int32_t

index

)

maxWait1h()

int64_t BaseLib::IQueue::maxWait1h

(

int32_t

index

)

maxWait1m()

int64_t BaseLib::IQueue::maxWait1m

(

int32_t

index

)

processingThreadCount()

uint32_t BaseLib::IQueue::processingThreadCount

(

int32_t

index

)

Returns the number of processing threads.

Returns

The number of processing threads for this queue.

processQueueEntry()

virtual void BaseLib::IQueue::processQueueEntry ( int32_t  index, std::shared_ptr< IQueueEntry > &  entry  )

pure virtual

This method is called by the processing threads for each item to process.

It needs to be implemented by the derived class.

Parameters

index	The index of the queue.
entry	The queued item to process.

queueEmpty()

bool BaseLib::IQueue::queueEmpty

(

int32_t

index

)

Checks if a queue is empty.

Parameters

index

The index of the queue to check.

Returns

Returns true if the queue is empty.

queueIsStarted()

bool BaseLib::IQueue::queueIsStarted

(

int32_t

index

)

Checks if the specified queue has been started.

queueSize()

int32_t BaseLib::IQueue::queueSize

(

int32_t

index

)

Returns the number of items queued in a queue.

Parameters

index

The index of the queue to check.

Returns

Return the number of queued items.

startQueue() [1/2]

void BaseLib::IQueue::startQueue	(	int32_t	index,
		bool	waitWhenFull,
		uint32_t	processingThreadCount,
		int32_t	threadPriority = 0,
		int32_t	threadPolicy = SCHED_OTHER
	)

Starts the threads of a queue.

Parameters

index	The index of the queue to start. The number of queues is defined by queueCount in the constructor.
waitWhenFull	When set to true, enqueue() waits until the queue is empty enough to queue the provided item. This takes precedence over the argument waitWhenFull of enqueue().
processingThreadCount	The number of processing threads to start.
threadPriority	The thread priority to set. Default is 0 (= disabled). The thread priority values depends on threadPolicy. See man sched for more details.
threadPolicy	The thread policy to use. Default is SCHED_OTHER (= disabled). See man sched for more details.

startQueue() [2/2]

void BaseLib::IQueue::startQueue	(	int32_t	index,
		bool	waitWhenFull,
		uint32_t	initialProcessingThreadCount,
		uint32_t	maxProcessingThreadCount
	)

Starts the threads of a queue using a thread count that can be increased later.

Parameters

index	The index of the queue to start. The number of queues is defined by queueCount in the constructor.
waitWhenFull	When set to true, enqueue() waits until the queue is empty enough to queue the provided item. This takes precedence over the argument waitWhenFull of enqueue().
initialProcessingThreadCount	The number of processing threads to start with the call of this method.
maxProcessingThreadCount	The number maximum number of processing threads that can be started.

stopQueue()

void BaseLib::IQueue::stopQueue

(

int32_t

index

)

Stops the threads of a queue previously started with startQueue().

Parameters

index

The index of the queue to stop.

threadLoad()

double BaseLib::IQueue::threadLoad

(

int32_t

index

)

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

• IQueue.h
• IQueue.cpp