Dear user, please, do not use the mpirun command on BCX. If you do it, you put all processes required on single node. Best, Ivan -- Ivan Girotto - i.girotto a cineca.it - Tel.+39 051 6171369 Supercomputing Group - superc a cineca.it CINECA - www.cineca.it Via Magnanelli 6/3 - Tel.+39 051 6171411 40033 Casalecchio di Reno - Fax.+39 051 6137273 Bologna - Italy