Now, after successfully build of 3.8.0-beta2 for my home dated
Intel(R) Core(TM) i5 CPU 750 @ 2.67GHz, I would like to ask you how to
make a build for powerful architecture which supports more advanced
instructions set.

If I understand well, CPU optimization is switched on by default. The
question is: how to get the most from a particular CPU - are there any
options or defines to turn on support of particular architecture
features ?

Now I see in the following, when asking 'povray --help':
Dynamic optimizations:
CPU detected: AMD,FMA4
Noise generator: generic (portable)
--
YB

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hi,

yesbird wrote:
> Now, after successfully build of 3.8.0-beta2 for my home dated
> Intel(R) Core(TM) i5 CPU 750 @ 2.67GHz, ...
> Now I see in the following, when asking 'povray --help':
> Dynamic optimizations:
> CPU detected: AMD,FMA4
> Noise generator: generic (portable)

strange.  on my "elderly" i5, the help option reports CPU Intel (with
SSE2,AVX,AVX2,FMA3) and noise generator 'avx2fma3-intel'.

fwiw, when the correct CPU is detected, find out which "chipset" ('Haswell' for
this machine), and check if the compiler "knows" that, ie I can use the
'-march=haswell -mtune=haswell' GCC options.  unsure about "performance boost"
:-).


regards, jr.

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On 09/11/2025 15:47, jr wrote:
> strange.  on my "elderly" i5, the help option reports CPU Intel (with
> SSE2,AVX,AVX2,FMA3) and noise generator 'avx2fma3-intel'.
> 
> fwiw, when the correct CPU is detected, find out which "chipset" ('Haswell' for
> this machine), and check if the compiler "knows" that, ie I can use the
> '-march=haswell -mtune=haswell' GCC options.  unsure about "performance boost"
> :-).

Nothing strange - at home I have Intel, but now building version for
hosting provider's server that works under "AMD EPYC 7763 64-Core" and
want to make optimal configuration.

I will be happy if you suggest me the best options for this
hardware.
-- 
YB

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