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Created by Iakov Davydov@idavydovGuest

uses all available CPU's even if -nt 1 with OpenBLAS

If fastcodeml is compiled with OpenBLAS it uses all available CPU's irrespective of -nt option.

It's a default behavior of OpenBLAS to use all CPU's. That's especially problematic since

  1. OpenBLAS is the default BLAS implementation in Ubuntu
  2. Most CPUs have hyper-threading which doesn't give a real advantages. Instead huge number of processes is making things significantly slower.

One work-around is to run fastcodeml with OMP_NUM_THREADS=1, but it only works if you need one thread.

I consider this bug to be important, because it prevents most users from using a parallel version of fastcodeml.