[fpc-devel] Are x86 optimizations across various platforms shared?

[Mark Morgan Lloyd]

Graeme Geldenhuys wrote:

> Both OS's run FPC 2.6.0 and the exact same revision of tiOPF, FPTest and
> fpGUI. fpGUI is used for the GUI test runner of FPTest.
> 
> Here is the summary of the unit test results, and the times it took in
> minutes and seconds.
> 
> No of tests  |  Type of Tests  |  Linux     |   FreeBSD
> -------------+-----------------+------------+----------------
>   151        | CSV persistence |    0:22    |    0:27
> -------------+-----------------+------------+----------------
>   151        | TAB persistence |    0:22    |    0:27
> -------------+-----------------+------------+----------------
>   151        |    XMLLight     |    0:23    |    0:26
> -------------+-----------------+------------+----------------
>   151        | SqlDB-Firebird  |    3:14    |    3:38
> -------------+-----------------+------------+----------------
>   682        | Non-Persistent  |    1:09    |    1:30
> -------------+-----------------+------------+----------------
> 
> As you can see, consistently the FreeBSD tests take longer than the
> Linux ones. The test project on each platform was compiled with exactly
> the same compiler settings.

What exactly are we looking at there: 151 iterations inside a single 
program, or 151 programs? Assuming the former, I think the first thing 
to do is to run with different numbers of iterations to determine 
whether FreeBSD is imposing a "one-time charge" or if it's an overhead 
per iteration. Also it would probably be worth breaking the result out 
in the standard format shown by the unix  time  command.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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