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    <p>You should definitely return ElapsedMilliseconds instead of ElapsedTicks. The value returned by ElapsedTicks is dependent upon the Stopwatch frequency, which can be different on different systems. It will not necessarily correspond to the Ticks property of a Timespan or DateTime object.</p> <p>See <a href="http://msdn.microsoft.com/en-us/library/system.diagnostics.stopwatch.elapsedticks.aspx" rel="nofollow noreferrer">http://msdn.microsoft.com/en-us/library/system.diagnostics.stopwatch.elapsedticks.aspx</a>.</p> <p>If you <em>do</em> want the extra resolution of Ticks, you should return <code>watch.Elapsed.Ticks</code> (i.e. Timestamp.Ticks) instead of <code>watch.ElapsedTicks</code> (this might be one of the subtlest <em>potential</em> errors in .Net). From MSDN:</p> <blockquote> <p>Stopwatch ticks are different from DateTime.Ticks. Each tick in the DateTime.Ticks value represents one 100-nanosecond interval. Each tick in the ElapsedTicks value represents the time interval equal to 1 second divided by the Frequency.</p> </blockquote> <p>Other than that, I guess your code is fine, although I think you'd be including some of the method-calling overhead in your measurements, which might be significant if the methods themselves take very little time to execute. Also, you probably would want to exclude the first call to the method from your calculated average, but I'm not sure how you'd do that in your class.</p> <p>One last point, which would probably not be relevant to most uses of this class: Stopwatch runs a bit fast compared to the system time. On my computer, it gets about 5 seconds (that's <em>seconds</em>, not milliseconds) ahead after 24 hours, and on other machines this drift can be even larger. So it's a little misleading to say it's highly <em>accurate</em>, when it's actually just highly <em>granular</em>. For timing short-duration methods, this obviously wouldn't be a significant problem.</p> <p>And one more last point, which certainly <em>is</em> relevant: I've often noticed while benchmarking that I'll get a bunch of running times that are all clustered within a narrow range of values (e.g. 80, 80, 79, 82 etc.), but occasionally something else will happen in Windows (like opening another program or my anti-virus kicks on or something) and I'll get a value wildly out of whack with the others (e.g. 80, 80, 79, 271, 80 etc.). I think a simple solution to this outlier problem is to use the <em>median</em> of your measurements instead of the <em>mean</em>. I don't know if Linq supports this automatically or not.</p>
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    1. POC#: Is this benchmarking class accurate?
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    1. COYou have a point about the method-calling overhead. Can't really get away with that here though... I think... Anyways it shouldn't be much and the methods I am using it on now are either so fast that I don't care if it is inaccurate or not, or so long that the method-calling overhead is tiny in comparison :p
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    2. CO@Svish: the overhead of the method-calling is suprisingly large. To see the difference, trying timing a loop where you multiply two numbers inline vs. passing the two numbers to a method as parameters and multiplying inside that method.
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    3. CO+1 for the catch of ElapsedTicks v. Elapsed.Ticks. Also, have you tried using a percentile to weed out the 'edge' cases? e.g. 90% of iterations were at, or below, a threshold. See http://www.techbookreport.com/tutorials/quantiles.html though I cheat and just use Excel. :)
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