线程c中的高CPU使用率#

时间:2014-04-09 15:57:13

标签: c# multithreading cpu-usage

你好我在运行这个线程时有很高的CPU使用率(15-16%),它是一个应该保持循环的线程,除非" ssStop"设置为true(有效),但是,当它运行时,我打开任务管理器,我看到该程序正在耗尽15%的计算机处理能力,一旦线程被占用,它就会下降到1-2%退出。即使使用我发现在线搜索此问题的EventWaitHandle,它仍然很高,有人知道我在这里做错了吗?:

public void Receive()
{
    try
    {              
        bool firstTimeRun = true;
        TcpListener ssTcpListener = new TcpListener(IPAddress.Any, 1500);
        TcpClient tcpReceiver;
        ssTcpListener.Start();
        while (!ssStop)
        {
            //Start listening for connection.
            //Accept any incoming connection requests on port 1500.
            tcpReceiver = new TcpClient();
            if (ssTcpListener.Pending())
            {
                tcpReceiver = ssTcpListener.AcceptTcpClient();
            }
            if (tcpReceiver.Connected)
            {
                //looped for first time; receives whole image.
                if (firstTimeRun)
                {
                    //TCP connected. Receive images from contact
                    NetworkStream receivedNs = new NetworkStream(tcpReceiver.Client);
                    Bitmap image = new Bitmap(receivedNs);
                    receivedImage = image;
                    pboScrnShare.Image = image;
                    receivedNs.Flush();
                    firstTimeRun = false;                            
                }
                //second time or higher looped; receives difference and overlays it.
                else if (!firstTimeRun)
                {
                    NetworkStream receivedNs = new NetworkStream(tcpReceiver.Client);

                    //Put image into picturebox.
                    receivedImage2 = new Bitmap(receivedNs);
                    receivedImage2.MakeTransparent(Color.Black);
                    Bitmap overlayedImage = new Bitmap(receivedImage.Width, receivedImage.Height);

                    using (Graphics gr = Graphics.FromImage(overlayedImage))
                    {
                        gr.DrawImage(receivedImage, new Point(0, 0));
                        gr.DrawImage(receivedImage2, new Point(0, 0));
                    }


                    try
                    {
                        pboScrnShare.Image = overlayedImage;
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show(ex.Message, "pbo second run");
                    }
                    receivedImage2.Dispose();
                    if (this.InvokeRequired) { this.Invoke(new MethodInvoker(delegate() { receivedImage = overlayedImage; })); } else { receivedImage = overlayedImage; }
                    receivedNs.Flush();
                }
                tcpReceiver.Close();
            }
            myEventWaitHandle.WaitOne(10, true);
        }
        ssTcpListener.Stop();
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.ToString(), "Invited ReceiveSS()", MessageBoxButtons.OK, MessageBoxIcon.Error);
    }
}

1 个答案:

答案 0 :(得分:1)

您正在为连接刻录cpu周期忙轮询。考虑到大部分时间Pending返回false,你的循环就像这样旋转:

while (!ssStop)
{
    tcpReceiver = new TcpClient();
    myEventHandle.WaitOne(10, false);
}

现在如果myEventHandle未设置,那么WaitOne中的10ms延迟将有效地限制执行但我的猜测是设置事件以便WaitOne立即返回true

没有必要轮询连接,因为AcceptTcpClient将阻止等待连接。因此,如果您稍微更改了代码,它应该按预期工作:

while (!ssStop)
{
    TcpClient tcpReceiver = ssTcpListener.AcceptTcpClient(); // this blocks
    ...
}