Shutting Down LAM/MPI

6. SHUTTING DOWN LAM

It is extremely important that each MPI session must be shutdown using the LAM shutdown command wipe. To properly shutdown the current MPI session:

shell$ lamhalt

Unless some of your LAM/MPI nodes have crashed, this will successfully shut down LAM/MPI and return to a command prompt. If lamhalt hangs and does not return to a command prompt, you will need to use the wipe command:

shell$ wipe -v hostfile

You should observe that all of the hosts in your hostfile are killed. If you use the hostfile listed above, you should see:

LAM 7.1.4 - Indiana Univeristy

Executing tkill on n0 (node1.cluster.example.com)...
Executing tkill on n1 (node2.cluster.example.com)...
Executing tkill on n2 (node3.cluster.example.com)...
Executing tkill on n3 (node4.cluster.example.com)...
Executing tkill on n4 (node5.cluster.example.com)...

IMPORTANT: Please note that it is extremely important that you must terminate each MPI session with the lamhalt and/or wipe commands because leftover daemons will cause unpredictable results and possibly even crash the machines on subsequence MPI sessions. This is highly demonstrative of poor and unsocial computing practice.