KMP_PLACE_THREADS ignored: unsupported architecture?

Dear all,

I am trying to optimise the MPI/OpenMP configuration for my application and have encountered a strange problem when trying to use the KMP_PLACE_THREADS variable.

I discovered some error messages and was able to reproduce the problem with the following minimal example.

If I run the following command with any more than one MPI process (it actually completes without error with -n 1), I get the OpenMP error shown below.

mpirun -n 2 -env KMP_PLACE_THREADS=15c,4t  ./scaling

OMP: Warning #236: KMP_PLACE_THREADS ignored: unsupported architecture.
OMP: Warning #236: KMP_PLACE_THREADS ignored: unsupported architecture.

I am using MPSS 3.2.1 and ifort compiler version 14.0.2.

Any help would be greatly appreciated. 

Best regards,

Alastair