aliBuild O2 fails on Ubuntu 18.04 during Python-modules

Dear experts,

I am trying to build O2 on Ubuntu 18.04. After following the steps in Dario Berzano’s online guide, aliBuild tries to build Python-modules but fails with the error

FATAL: problems importing the following Python modules

  • keras
  • tensorflow

I already tried to manually install all the modules that are set as PIP_REQUIREMENTS using "pip3 install --user " but this also does not help. I guess my system is just missing some packages but I don’t know which.

The aliDoctor output and the Python-modules-latest log are in the cernbox.

Thank you very much for your help!



It looks like your machine does not support AVX instructions, which are enabled by default in the precompiled binaries for tensorflow. Given AVX is available on any (reasonable) CPU after 2011, I guess that’s a sensible choice. Do you happen to know what CPU you are using? Is it by chance a Celeron?

Unless you really need tensorflow and keras, I would simply comment out the packages from the recipe.


my CPU is a Intel Core i7.

I think for now it is sufficient to not use those packages. With this workaround python-modules was built successfully.

Thank you!