mpirun: How to select dedicated machines ?

Hi,

I just have successfully installed the PGI pi stuff. Everything is running fine,
but when I just tried the simple myname example, I saw that even if only 4 cores
are used everything is spreaded all over all machines.
But we have 4 node with 8 core’s and I want a job to use all local cpu’s until
more then 8 cores are used.

How can I do it ?

Bye, Peer

Hi Peer,

To clarify, your cluster consists of multiple 4 CPU dual-core systems. However, when you run using “mpirun -np n”, the processes are being allocated on each system instead of first being allocated to system 1 and then to system 2 once you’ve reached the 9th process.

If this is the case, then update your machines file to include the number of CPUs per system or list each system 8 times. For example:

system1:8
system2:8

or

system1
system1
system1
system1
...etc

Hope this helps,
Mat