What is the best way to measure execution time of a function?

Question

Obviously I can do and DateTime.Now.After - DateTime.Now.Before but there must be something more sophisticated.

Any tips appreciated.

score 96 · Accepted Answer · edited May 23 '17 at 12:25

96

System.Environment.TickCount and the System.Diagnostics.Stopwatch class are two that work well for finer resolution and straightforward usage.

See Also:

edited May 23 '17 at 12:25

Community

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answered Dec 19 '08 at 13:12

ctacke

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tafa · Answer 2 · 2008-12-19T13:23:04.320

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I would definitely advise you to have a look at System.Diagnostics.Stopwatch

And when I looked around for more about Stopwatch I found this site;

Beware of the stopwatch

There mentioned another possibility

Process.TotalProcessorTime

edited Dec 19 '08 at 13:23

answered Dec 19 '08 at 13:14

tafa

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The article is updated - stopwatch has been improved. – kwesolowski Jul 25 '15 at 21:45
Could you tell me the difference about `TotalProcessorTime` and `Stopwatch`? I have not search any information.. – yode Oct 30 '17 at 18:29

score 10 · Answer 3 · answered Dec 19 '08 at 13:18

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Use a Profiler

Your approach will work nevertheless, but if you are looking for more sophisticated approaches. I'd suggest using a C# Profiler.

The advantages they have is:

You can even get a statement level breakup
No changes required in your codebase
Instrumentions generally have very less overhead, hence very accurate results can be obtained.

There are many available open-source as well.

answered Dec 19 '08 at 13:18

M.N

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There are also disadvantages to using a profiler: the information is _post factum_, instrumentation is necessary still, not suitable to be kept in production code (we may want to measure working applications, not just during development). And last: profiling may sometimes be overkill. – Tomasz Gandor Mar 04 '13 at 11:44

score 4 · Answer 4 · answered Dec 19 '08 at 13:16

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Tickcount is good, however i suggest running it 100 or 1000 times, and calculating an average. Not only makes it more measurable - in case of really fast/short functions, but helps dealing with some one-off effects caused by the overhead.

answered Dec 19 '08 at 13:16

FooLman

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What is the best way to measure execution time of a function?

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