多线程中的变量范围,为什么我的对象引用丢失?

简单地说,在一个生产者-消费者场景下,我使用一个可变的对象在生产者和消费者之间同步和传递数据和消息。共享缓冲区是 ConcurrentQueue 字节数组的。实现循环缓冲区,防止堆碎片和频繁的对象交换 GC 我用过 ConcurrentBag 字节数组作为已用字节数组的回收站。 ManualResetEventSlim 用于线程同步。有时我会在代码中丢失对字节数组的引用。下面是我的代码的简化版本,以防您需要更多的细节,但我猜这是处理线程时的一个常规错误。

MutableObject mutableObject = new MutableObject();

Producer producer = MutableObject.GetProducer();
Consumer consumer = MutableObject.GetConsumer();

Thread fork = new Thread(new ThreadStart(producer.Start));

// Forking execution path
fork.Start();
// Main thread goes here
consumer.Start();


class MutableObject()
{
    private Producer m_producer;
    private Consumer m_consumer;
    private ConcurrentBag<byte[]> m_recycleBin = new ConcurrentBag<byte[]>();
    private ConcurrentQueue<byte[]> m_sharedBuffer = new ConcurrentQueue<byte[]>();

    public Producer GetProducer()
    {
        // Keep a reference to the mutable object
        return new Producer(this);
    }

    // GetConsumer() method is just like GetProducer() method

    public void GetEmptyBuffer(out byte[] buffer)
    {
        if (!m_recycleBin.TryTake(out buffer))
            buffer = new byte[1024];
    }

    public bool Put(byte[] buffer)
    {
        m_sharedBuffer.Enqueue(buffer);
        // Set ManualResetEventSlim for consumer
    }

    public bool Get(byte[] buffer) // Consumer calls this method in a loop
    {
        m_sharedBuffer.TryDequeue(out buffer);
        // I save a reference to buffer here and pass it to recyclebin at next call like this: lastBuffer = buffer;
        // This is because buffers are passing by refrence for I should wait until it would be used by consumer.
        m_recycleBin.Add(lastBuffer);
        // Set ManualResetEventSlim for producer
    }
}

class Producer
{
    private MutableObject m_mutableObject;

    public Producer(MutableObject mutableObject)
    {
        m_mutableObject = mutableObject;
    }

    public void Start()
    {
        byte[] buffer;

        while (true)
        {
            m_mutableObject.GetEmptyBuffer(out buffer);
            m_mutableObject.Put(buffer);
        }
    }
}

事实上 GetEmptyBuffer() 方法经常创建新的缓冲区,虽然已使用的缓冲区存储在回收站中,但回收站计数有时不会增加!