Class SleepingWaitStrategy

  • All Implemented Interfaces:
    WaitStrategy

    public final class SleepingWaitStrategy
    extends Object
    implements WaitStrategy
    Sleeping strategy that initially spins, then uses a Thread.yield(), and eventually sleep (LockSupport.parkNanos(1)) for the minimum number of nanos the OS and JVM will allow while the EventProcessors are waiting on a barrier.

    This strategy is a good compromise between performance and CPU resource. Latency spikes can occur after quiet periods.

    • Constructor Detail

      • SleepingWaitStrategy

        public SleepingWaitStrategy()
      • SleepingWaitStrategy

        public SleepingWaitStrategy​(int retries)
    • Method Detail

      • waitFor

        public long waitFor​(long sequence,
                            Sequence cursor,
                            Sequence dependentSequence,
                            SequenceBarrier barrier)
                     throws AlertException,
                            InterruptedException
        Description copied from interface: WaitStrategy
        Wait for the given sequence to be available. It is possible for this method to return a value less than the sequence number supplied depending on the implementation of the WaitStrategy. A common use for this is to signal a timeout. Any EventProcessor that is using a WaitStrategy to get notifications about message becoming available should remember to handle this case. The BatchEventProcessor explicitly handles this case and will signal a timeout if required.
        Specified by:
        waitFor in interface WaitStrategy
        Parameters:
        sequence - to be waited on.
        cursor - the main sequence from ringbuffer. Wait/notify strategies will need this as it's the only sequence that is also notified upon update.
        dependentSequence - on which to wait.
        barrier - the processor is waiting on.
        Returns:
        the sequence that is available which may be greater than the requested sequence.
        Throws:
        AlertException - if the status of the Disruptor has changed.
        InterruptedException - if the thread is interrupted.