After digging into the source, I did not find any march option, but there is a MUJOCO_ENABLE_AVX variable that I can set to OFF (which I guess should disable both AVX-512 and AVX). I added this to the guix package, but it did not change anything. I also tried to add a march option in the compilation options and same it did not change anything. I did not find how to make sure that AVX was indeed disabled though, I hope the option was really applied.
So I don't know, it may be that the cause is not AVX but something that computer with AVX-512 have? Or maybe some dependency use AVX-512 but there are a lot of dependencies, I can't manually check the source on all of them. I will continue my investigation. Thanks for the help, Timothée ----- Mail original ----- > De: "Ludovic Courtès" <ludovic.cour...@inria.fr> > À: "Timothee Mathieu" <timothee.math...@inria.fr> > Cc: "Andreas Enge" <andr...@enge.fr>, "Steve George" <st...@futurile.net>, > "Cayetano Santos" <csant...@inventati.org>, > "help-guix" <help-guix@gnu.org> > Envoyé: Mercredi 14 Mai 2025 12:00:19 > Objet: Re: Reproducibility of guix shell container across different host OS > Hi Timothée, > > Timothee Mathieu <timothee.math...@inria.fr> writes: > >> I am not sure if I understand everything about AVX, I tried to tune >> the compilation to CPU without AVX with >> https://hpc.guix.info/blog/2022/01/tuning-packages-for-a-cpu-micro-architecture/ >> in order to get reproducible results, but it did not work, maybe >> because only a few of the dependency packages are tunable. Is there a >> way to force everything to use AVX and not AVX-512? I understand that >> AVX-512 is meant to be faster but I think in my case before being >> faster I want to see if it is possible to be reproducible. > > As the article above suggests, packages in Guix are in general built for > the “baseline” x86_64 instruction set (so without AVX-512 extensions). > > Sometimes that requires small modifications to the package’s build > system because some of them explicitly pass flags like ‘-march=native’, > which ends up producing code for whatever extensions the build machine > supports rather than for the baseline instruction set. > > It may be that you need to tweak your mujoco package along these lines? > > HTH, > Ludo’.
