public override long Receive(long ticket, T batch)
{
long time = nanoTime();
while (QueuedBatches.get() >= _maxQueueLength)
{
Park.park(_receiverThread = Thread.CurrentThread);
}
// It is of importance that all items in the queue at the same time agree on the number of processors. We take this lock in order to make sure that we
// do not interfere with another thread trying to drain the queue in order to change the processor count.
long @lock = ApplyProcessorCount(_stripingLock.readLock());
QueuedBatches.incrementAndGet();
Unit unit = new Unit(this, ticket, batch, _numberOfForkedProcessors);
// [old head] [unit]
// ^
// head
Unit myHead = _head.getAndSet(unit);
// [old head] -next-> [unit]
myHead.Next = unit;
_stripingLock.unlock(@lock);
return(nanoTime() - time);
}
private void DecrementQueue()
{
// Even though queuedBatches is built into AbstractStep, in that number of received batches
// is number of done + queued batches, this is the only implementation changing queuedBatches
// since it's the only implementation capable of such. That's why this code is here
// and not in AbstractStep.
int queueSizeAfterThisJobDone = QueuedBatches.decrementAndGet();
Debug.Assert(queueSizeAfterThisJobDone >= 0, "Negative queue size " + queueSizeAfterThisJobDone);
if (queueSizeAfterThisJobDone == 0)
{
_lastBatchEndTime.set(currentTimeMillis());
}
}
