c# socket 通常使用半天 程序会自动关闭

c# socket 正常使用半天 程序会自动关闭
放在windows 2008server 上的，16G内存  半天就自动挂掉了，报错CLR20r3 和System.OutOfMemoryException

        IPAddress ip1;

        private bool isExit = false;

        TcpListener listener;

        private ManualResetEvent allDone = new ManualResetEvent(false);


myThread = new Thread(new ThreadStart(AcceptConnection));

            myThread.Start();


 private void AcceptConnection()

        {


            IPHostEntry ipHost = Dns.Resolve(Dns.GetHostName());

            ipHost.AddressList[0];

            ip1 = IPAddress.Parse("172.19.58.164");


            listener = new TcpListener(ip1, 3001);


            listener.Start();

            while (isExit == false)

            {

                try

                {

                    allDone.Reset();

                    Application.DoEvents();

                    AsyncCallback callback = new AsyncCallback(AcceptTcpClientCallBack);

                    listener.BeginAcceptTcpClient(callback, listener);

                    allDone.WaitOne();

                }

                catch (Exception e)

                {

                    break;

                }

            }

        }   


private void AcceptTcpClientCallBack(IAsyncResult iar)

        {

            try

            {

                allDone.Set();

                TcpListener mylistener = (TcpListener)iar.AsyncState;

                TcpClient client = mylistener.EndAcceptTcpClient(iar);

                DataReadWrite datareadwrite = new DataReadWrite(client);

                datareadwrite.ns.BeginRead(datareadwrite.read, 0, datareadwrite.read.Length, ReadCallBack, datareadwrite);

            }

            catch (Exception e)

            {

                return;

            }

        }


private void ReadCallBack(IAsyncResult iar)

        {

            string revstring = string.Empty;

            string msg = string.Empty;

            try

            {

                DataReadWrite datareadwrite = (DataReadWrite)iar.AsyncState;

                int recv = datareadwrite.ns.EndRead(iar);

                revstring.Remove(0, revstring.Length);