Cross-Compiling x86_64 but for different CPU

Cross-Compiling x86_64 but for different CPU

[Zaid M]

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I have an Intel CPU but I want to compile an optimized binary for AMD
(x86_64) which may have a different CPU instruction set (e.g. avx512 or
avx512bw) and I don't want to use "-Dplatform=generic". How can I achieve
that?

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Re: Cross-Compiling x86_64 but for different CPU

[Dmitry Kozlyuk]

2024-12-31 11:45 (UTC+0300), Zaid M:
> I have an Intel CPU but I want to compile an optimized binary for AMD
> (x86_64) which may have a different CPU instruction set (e.g. avx512 or
> avx512bw) and I don't want to use "-Dplatform=generic". How can I achieve
> that?

When you use `-Dplatform=generic`, parts of DPDK vectorized for e.g. AVX512
are still built, and DPDK will employ them if run on a CPU that supports them.
Usually this is enough because fast-path routines have vectorized versions
and the performance of other code is not critical, but not always.
If you know that the host machine (AMD) has e.g. Zen3 instruction set,
you can use `-Dcpu_instruction_set=zen3` to optimize the rest of DPDK code.
This will make the build non-portable to machines without Zen3 though.

P.S. Questions about DPDK usage belong to users@dpdk.org.