How do I measure how long a function is running?

Question

I want to see how long a function is running. So I added a timer object on my form, and I came out with this code:

private int counter = 0;

// Inside button click I have:
timer = new Timer();
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
Result result = new Result();
result = new GeneticAlgorithms().TabuSearch(parametersTabu, functia);
timer.Stop();

And:

private void timer_Tick(object sender, EventArgs e)
{
    counter++;
    btnTabuSearch.Text = counter.ToString();
}

But this is not counting anything. Why?

Ludmilla

if you set timer.stop(); after Start() is normal. When is necessary to stop timer? When function is finished? – Cockswain

why not StopWatch? (msdn.microsoft.com/en-us/library/…) – Baram

Possible duplicate of Measuring code execution time – Kellner

Possible duplicate of Calculate the execution time of a method – Dodson

Answer 1

To avoid future problems with a timer, here is the right code:

timer = new Timer();
timer.Tick += new EventHandler(timer_Tick);
timer.Interval = 1; //set interval on 1 milliseconds
timer.Enabled = true; //start the timer
Result result = new Result();
result = new GeneticAlgorithms().TabuSearch(parametersTabu, functia);
timer.Enabled = false; //stop the timer

---

private void timer_Tick(object sender, EventArgs e)
{
   counter++;
   btnTabuSearch.Text = counter.ToString();
}

But it's the wrong aproach. You must use the Stopwatch (System.Diagnostic) class because it's a High resolution timer and the word Diagnostic says everything.

So try this:

Stopwatch timer = Stopwatch.StartNew();

Result result = new Result();
result = new GeneticAlgorithms().TabuSearch(parametersTabu, functia);

timer.Stop();  
TimeSpan timespan = timer.Elapsed;

btnTabuSearch.Text = String.Format("{0:00}:{1:00}:{2:00}", timespan.Minutes, timespan.Seconds, timespan.Milliseconds / 10);

Altissimo

Note: with the timer set with an interval of 1ms, you should be careful not to think that your counter is actually the number of milliseconds. Depending on hardware, the minimum interval for a timer (on my computer) is around 15ms. So even if you set the interval to 1ms, it'll only fire every 15ms or so. – Keelboat

i will try the timer tomorrow. I just want a counter to see how much time passed since i pressed the button. – Ludmilla

var timer = Stopwatch.StartNew(); <-- one less line of code – Polack

The answaer is not correct. Timer() code does not work anymore. – Looming

Answer 2

Don't use a timer - use the Stopwatch class.

var sw = new Stopwatch();
Result result = new Result();

sw.Start();
result = new GeneticAlgorithms().TabuSearch(parametersTabu, functia);

sw.Stop();

// sw.Elapsed tells you how much time passed

Clavicorn

Or even var sw = Stopwatch.StartNew(); <-- one less line of code – Polack

Answer 3

The best way to see how long a bit of code takes to run is to use System.Diagnostics.Stopwatch.

Here's an example:

using System.Diagnostics;

#if DEBUG
     Stopwatch timer = new Stopwatch();
     timer.Start();
#endif

     //Long running code

#if DEBUG
     timer.Stop();
     Debug.WriteLine("Time Taken: " + timer.Elapsed.TotalMilliseconds.ToString("#,##0.00 'milliseconds'"));
#endif

I use the #if DEBUG to ensure the stopwatch code doesn't get into the production release, but you could do without it.

Limbert

Answer 4

Visual Studio 2015, 2017 Professional and Enterprise has diagnostic tool. If you have a breakpoint at the end of your function, it will display the time and duration under the Events tab as shown in the image:

You can see the article Diagnostic Tools debugger window in Visual Studio 2015 for more details.

PS; So far only Xamarin forms, cross platform project doesnt support this feature. I wish that Microsoft brings this great feature for xamarin forms projects as well.

Alden

this has been a long time coming – Undertaker

Answer 5

You should use the stopwatch class for timing functions.

Try the following:

private int counter = 0;

// setup stopwatch and begin timing
var timer = System.Diagnostics.Stopwatch.StartNew();

Result result = new Result();
result = new GeneticAlgorithms().TabuSearch(parametersTabu, functia);

// stop timer and get elapsed time
timer.Stop();
var elapsed = timer.Elapsed;

// display result time
MessageBox.Show(elapsed.ToString("mm':'ss':'fff"));

Snappish

Answer 6

Use Stopwatch of System.Diagnostics:

static void Main(string[] args)
{
    Stopwatch stopWatch = new Stopwatch();
    stopWatch.Start();
    Thread.Sleep(10000);
    stopWatch.Stop();

    // Get the elapsed time as a TimeSpan value.
    TimeSpan ts = stopWatch.Elapsed;

    // Format and display the TimeSpan value.
    string elapsedTime = String.Format("{0:00}:{1:00}:{2:00}.{3:00}",
        ts.Hours, ts.Minutes, ts.Seconds,
        ts.Milliseconds / 10);
    Console.WriteLine("RunTime " + elapsedTime);
}

Englebert

Wouldn't it be easier to print the time with ts.ToString("hh:mm:ss.ff") or ts.ToString("G")? – Necromancy

Answer 7

For timing a function, you should use the Stopwatch Class

Also, the reason your timer isn't counting is because you didn't set an interval for it.

Keelboat

Answer 8

A possibility is to write once an helper method like that:

    public static void Time(Action action)
    {
        Stopwatch st = new Stopwatch();
        st.Start();
        action();
        st.Stop();
        Trace.WriteLine("Duration:" + st.Elapsed.ToString("mm\\:ss\\.ff"));
    }

and use it everywhere else to mesure the time like that:

    Time(() =>
    {
     CallOfTheMethodIWantToMeasure();
    });

Renaerenaissance

Answer 9

I reviewed and agreed with all suggestions. But wanted to share one generic implementation for execution time logger where we do not want to implement Stopwatch logic multiple times but still wants to measure execution time for multiple methods.

The main reason for not to implement logger in generic way is - method execution is in between stopwatch.Start() and stopwatch.Stop() also we may require method result after the execution for further processing.

So to tackle this issue I created following sample implementation where Execution time is logged separately without mixing it with actual method flow.

public static class Helper
{
    public static T Time<T>(Func<T> method, ILogger log)
    {
        var stopwatch = new Stopwatch();
        stopwatch.Start();
        var result = method();
        stopwatch.Stop();
        log.Info(string.Format("Time Taken For Execution is:{0}", stopwatch.Elapsed.TotalMilliseconds));
        return result;
    }
}

public class Arithmatic
{
    private ILogger _log;
    public Arithmatic(ILogger log)//Inject Dependency
    {
        _log = log;
    }

    public void Calculate(int a, int b)
    {
        try
        {
            Console.WriteLine(Helper.Time(() => AddNumber(a, b), _log));//Return the result and do execution time logging
            Console.WriteLine(Helper.Time(() => SubtractNumber(a, b), _log));//Return the result and do execution time logging
        }
        catch (Exception ex)
        {
            _log.Error(ex.Message, ex);
        }
    }

    private string AddNumber(int a, int b)
    {
        return "Sum is:" + (a + b);
    }

    private string SubtractNumber(int a, int b)
    {
        return "Subtraction is:" + (a - b);
    }
}

public class Log : ILogger
{
    public void Info(string message)
    {
        Console.WriteLine(message);
    }

    public void Error(string message, Exception ex)
    {
        Console.WriteLine("Error Message:" + message, "Stacktrace:" + ex.StackTrace);
    }
}

public interface ILogger
{
    void Info(string message);
    void Error(string message, Exception ex);
}

Calling Part:

 static void Main()
 {
    ILogger log = new Log();
    Arithmatic obj = new Arithmatic(log);
    obj.Calculate(10, 3);
    Console.ReadLine();
 }

Swatow

interesting idea. Thanks for posting. – Ludmilla

don't you think the code contains too much unrelated info, I believe only the helper method and its usage in one line is enough – Diedrediefenbaker

Some extend i agree but information is not unrelated if one wants to use this concept at broader/enterprise level then he has to consider all this information like logger and all. So I just mentioned detailed way of implementation. – Swatow

Answer 10

record the time when current step begins to process

DateTime dtStart = DateTime.Now;

//Calculate the total number of milliseconds request took (Timespan = to represent the time interval)-> current - started time stamp ...
//TotalMilliseconds -->Gets the value of the current TimeSpan structure expressed in whole and fractional milliseconds.
// to measure how long a function is running 
var result=((TimeSpan)(DateTime.Now - dtStart)).TotalMilliseconds.ToString("#,##0.00") + "ms";

Ghee

Answer 11

To view elapsed milliseconds betweeen breakpoints when debugging code, Visual Studio provides PerfTips, it's a built-in, useful and fast tool.

Tow