jhorstmann commented on issue #10841:
URL: https://github.com/apache/arrow-rs/issues/10841#issuecomment-5417529355

   I would also prefer not doing multiple versions of every compute kernel, as 
that could multiply compile times. Runtime dispatch should be reserved for 
kernels where it enables a big improvement in performance, possibly bigger than 
simply recompiling with avx2 vs sse2 or avx512 instead of avx2. Otherwise I see 
the risk of added complexity everywhere, for performance improvements in the 
10%-20% range.
   
   Runtime dispatch also introduces problems for testing and code coverage. The 
detection might need to be overridden (for example via environment variables), 
and tests run multiple times.
   
   I think we can continue recommending users to set a reasonable baseline 
target-cpu, like x86-64-v3 on Intel/AMD hardware. The [Steam Hardware 
Survey](https://store.steampowered.com/hwsurvey/Steam-Hardware-Software-Survey-Welcome-to-Steam)
 shows avx2 and bmi2 at ~95%, so compile-time detection for bmi instructions 
for example should be fine.


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