From now on, two new system-wide defaults will be set for programs using the OpenMP (open multi-processing) parallelization model:

export OMP_PROC_BIND=true
export OMP_PLACES=cores

This affects programs parallelized only with OpenMP, as well as hybrid applications using OpenMP and MPI.

These settings should yield better parallel computing efficiency, particularly in those cases where as yet no explicit CPU binding was set.

In general, there are no adverse side effects to be expected. If that's the case nonetheless, you can disable the new defaults by unsetting these variables in your job scripts with:

unset OMP_PROC_BIND
unset OMP_PLACES