Class IoQueue

quantum/quantum_io_queue.h:40–110

============================================================================================== class IoQueue ============================================================================================== @class IoQueue @brief Thread queue for executing IO tasks. @note For internal use only.

/// @brief Thread queue for executing IO tasks.
/// @note For internal use only.
class IoQueue : public IQueue
{
public:
    using TaskList = std::list<IoTask::Ptr, IoQueueListAllocator>;
    using TaskListIter = TaskList::iterator;
    
    IoQueue();
    
    IoQueue(const Configuration& config,
            std::vector<IoQueue>* sharedIoQueues);
    
    IoQueue(const IoQueue& other);
    
    IoQueue(IoQueue&& other) = default;
    
    ~IoQueue();
    
    void terminate() final;
    
    void pinToCore(int coreId) final;
    
    void run() final;
    
    void enqueue(ITask::Ptr task) final;
    
    bool tryEnqueue(ITask::Ptr task) final;
    
    ITask::Ptr dequeue(std::atomic_bool& hint) final;
    
    ITask::Ptr tryDequeue(std::atomic_bool& hint) final;
    
    size_t size() const final;
    
    bool empty() const final;
    
    IQueueStatistics& stats() final;
    
    SpinLock& getLock() final;
    
    void signalEmptyCondition(bool value) final;
    
    bool isIdle() const final;
    
    const std::shared_ptr<std::thread>& getThread() const final;
    
private:
    ITask::Ptr grabWorkItem();
    ITask::Ptr grabWorkItemFromAll();
    void doEnqueue(ITask::Ptr task);
    ITask::Ptr doDequeue(std::atomic_bool& hint);
    ITask::Ptr tryDequeueFromShared();
    std::chrono::milliseconds getBackoffInterval();
    
    //async IO queue
    std::vector<IoQueue>*           _sharedIoQueues;
    bool                            _loadBalanceSharedIoQueues;
    std::chrono::milliseconds       _loadBalancePollIntervalMs;
    Configuration::BackoffPolicy    _loadBalancePollIntervalBackoffPolicy;