[Beowulf] Here we go again

[Miguel Dias Costa]

On 13/12/2019 00:29, Peter Kjellström wrote:
> But setting MKL_DEBUG_CPU_TYPE=5 has an effect (essentially turns off
> cpu detect and sets it to type 5, which is AVX2).

I have been using MKL_DEBUG_CPU_TYPE=5 on Naples with the 2018 versions 
of MKL with good results, but when switching to 2019 versions some 
application tests started failing (dramatically wrong results) in FFT 
dependent stuff (and no failure without MKL_DEBUG_CPU_TYPE=5).

I could also reproduce this behaviour in some of MKL's own FFT examples, 
so it shouldn't be hard for other people to check.

Setting both MKL_DEBUG_CPU_TYPE=5 and MKL_CBWR=COMPATIBLE solved the 
issue, and MKL is still using AVX2, but it does mean one needs to be 
careful with MKL_DEBUG_CPU_TYPE...

My two (sing)cents,

Miguel