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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.compilers
Subject: Re: Not normal for the same program to be faster in C# than in C++ [Visual Studio 2019]
Date: Fri, 6 Aug 2021 16:14:22 +0200
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On 2021-08-06 04:58, George Neuner wrote:

> I would modify your programs like so (in pseudo):
>
>    total = 0
>    allocate array
>    for N iterations
>       initialize array
>       start = current time
>          run the seive
>       stop = current time
>       total += (stop - start)
>    average = total / N

Another technique is factoring out looping and other overheads by
running empty loop as a reference:

    start = current time
    for N iterations
       initialize array
       run the sieve
    end loop;
    total1 = start - current time

    start = current time
    for N iterations
       initialize array
    end loop;
    total2 = start - current time

    average = (total1 - total2) / N  -- sieve only

P.S. Optimizations is a usual suspect of ruining benchmark measures.

--
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de