localhost上UDP包丢失的原因？
在我的WPF 4.0应用程序中，我有一个UDP监听器，如下所示。 在我的Windows 7 PC上，我在localhost上运行服务器和客户端。
每个接收的数据报都是较大位图的扫描线，因此在接收到所有扫描线之后， UI线程上会显示位图。 这似乎有效。 但是，偶尔会丢失1-50％的扫描线。 我希望这在弱网络连接上，但在本地运行时不会。
使用以下代码可能导致UDP程序包丢失的原因是什么？
IPEndPoint endPoint = new IPEndPoint(IPAddress.Any, PORT); udpClient = new UdpClient(endPoint); udpClient.Client.ReceiveBufferSize = 65535; // I've tried many different sizes... var status = new UdpStatus() { u = udpClient, e = endPoint }; udpClient.BeginReceive(new AsyncCallback(UdpCallback), status); private void UdpCallback(IAsyncResult ar) { IPEndPoint endPoint = ((UdpStatus)(ar.AsyncState)).e; UdpClient client = ((UdpStatus)(ar.AsyncState)).u; byte[] datagram = client.EndReceive(ar, ref endPoint); // Immediately begin listening for next packet so as to not miss any. client.BeginReceive(new AsyncCallback(UdpCallback), ar.AsyncState); lock (bufferLock) { // Fast processing of datagram. // This merely involves copying the datagram (scanline) into a larger buffer. // // WHEN READY: // Here I can see that scanlines are missing in my larger buffer. } }
如果我在回调中放入System.Diagnostics.Debug.WriteLine ，则包丢失会急剧增加。 似乎这个回调中的一个小毫秒延迟会导致问题。 不过，我的发布版本中也出现了同样的问题。
UPDATE
当我稍微强调UI时，错误变得更加频繁。 是否在主线程上执行了UdpClient实例？
要避免线程阻塞问题，请尝试使用较新的IO完成端口接收方法的此方法：
private void OnReceive(object sender, SocketAsyncEventArgs e) { TOP: if (e != null) { int length = e.BytesTransferred; if (length > 0) { FireBytesReceivedFrom(Datagram, length, (IPEndPoint)e.RemoteEndPoint); } e.Dispose(); // could possibly reuse the args? } Socket s = Socket; if (s != null && RemoteEndPoint != null) { e = new SocketAsyncEventArgs(); try { e.RemoteEndPoint = RemoteEndPoint; e.SetBuffer(Datagram, 0, Datagram.Length); // don't allocate a new buffer every time e.Completed += OnReceive; // this uses the fast IO completion port stuff made available in .NET 3.5; it's supposedly better than the socket selector or the old Begin/End methods if (!s.ReceiveFromAsync(e)) // returns synchronously if data is already there goto TOP; // using GOTO to avoid overflowing the stack } catch (ObjectDisposedException) { // this is expected after a disconnect e.Dispose(); Logger.Info("UDP Client Receive was disconnected."); } catch (Exception ex) { Logger.Error("Unexpected UDP Client Receive disconnect.", ex); } } }