$ mpirun -host localhost -n 2 ./mpitest
Hello world: rank 0 of 2 running on knl-lb0.jf.intel.com
Hello world: rank 1 of 2 running on knl-lb0.jf.intel.com
FROM RANK 1 - numthreads = 32
FROM RANK 0 - numthreads = 32

Elapsed time from rank 0:    8246.90 (usec)
Elapsed time from rank 1:    8423.09 (usec)
rank 0 pi=   3.141613006592