任务与减少CPU使用率

Question

如果我问一个愚蠢的问题，请原谅我。我正在处理Task.I有一个代码如下：

private string result;
public string Result
{
      get { return result; }
      set
      {
        if (value != result)
        {
           result = value;
           OnRaise("Result");
        }
      }
}

的ICommand：

private ICommand _cmd;
public ICommand Cmd
{
      get
      {
         _cmd = _cmd ?? new RelayCommand(s => RunAction(), () => IsEnable);
         return _cmd;
      }
}

方法和任务：

int count = 0;
private async void RunAcion()
{
    IsEnable = false;
    var context = TaskScheduler.FromCurrentSynchronizationContext();           
    await Task.Run(() => Runcmd()).ContinueWith(s => this.Result =   count.ToString(), context);
    IsEnable = true;           
}
void Runcmd()
{
    Thread.Sleep(2000);
    count++;
}

MainWindow.xaml：

<Button x:Name="btnStart" Content="Start" 
    Height="50" IsEnabled="{Binding IsEnable}"
    Command="{Binding Cmd, Delay=1000}"
/>
<TextBlock Foreground="#4C4C4C" Text="{Binding Show}"/>

运行时获得50％的CPU。如何降低CPU使用率？