Why is my application becoming less responsive over time?

Question

I'm debugging a C# application that becomes almost unresponsive after a few days. The application calculates memory/CPU usage every second and displays it in the footer of the main UI.

The cause for the unresponsiveness is because of the time it takes to fetch the RawValue of a PerformanceCounter ("Working Set - Private"). After a couple of days, it takes almost a second to fetch the RawValue, freezing the main UI thread. If I restart my computer, everything is fast again for a few days until it slowly becomes less responsive. If I recompile this application without the PerformanceCounter code (it's open source), it runs normally immediately.

To rule out that it's the application, here's some sample code that does the exact same thing:

static void Main(string[] args)
{
    using (var memoryWorkingSetCounter = new PerformanceCounter("Process", "Working Set - Private", Process.GetCurrentProcess().ProcessName, true))
    {
        while (!Console.KeyAvailable)
        {
            var memoryWorkingSetSw = new Stopwatch();
            memoryWorkingSetSw.Start();
            var memoryWorkingSetValue = memoryWorkingSetCounter.RawValue;
            memoryWorkingSetSw.Stop();
            Console.WriteLine(memoryWorkingSetValue.ToString());
            Console.WriteLine(memoryWorkingSetSw.Elapsed.ToString());
            Thread.Sleep(TimeSpan.FromSeconds(1));
        }
    }
    Console.Read();
}

I left this running for ~2.5 days and graphed the Elapsed time in milliseconds:

What could cause a performance counter in Windows to become slow over time? Could another app be not cleaning it up? Is there a way to debug which apps are also looking at this performance counter? I'm on Windows 10.

Answer 1

why you declare Stopwatch inside a loop? remove any new declaration possible inside loops.

when you do so the memory is increasing overtime and you count on garbage collector to do the work