Basic Administration

openMosix provides the advantage of process migration to HPC-applications. The administrator can configure and tune the openMosix-cluster by using the openMosix-user-space-tools or the /proc/hpc interface.

Up till openMosix version 2.4.16 the /proc interface was named /proc/mosix ! Until openMosix version 2.4.17 it was named /proc/hpc.

The values in the flat files in the /proc/hpc/admin directory presenting the current configuration of the cluster. Hence the administrator can write its own values into these files to change the configuration during runtime, e.g.

echo 1 > /proc/hpc/admin/block

locks the arrival of remote processes

echo 1 > /proc/hpc/admin/bring
brings all migrated processes home

...

Next to changing values you can also get more information about your cluster from this interface.

cat /proc/hpc/nodes/[openMosix_ID]/CPUs 
shows you how many CPU's node "openMosix_ID" has

cat /proc/hpc/nodes/[openMosix_ID]/load
shows the openMosix load of this node. Other files include mem,rmem,speed,status,tmem,util etc ..

Within the /proc/$PID/ subsystem you can find important information about the status of a process, whether it locked (/proc/$PID/lock) or send to another node (/proc/$PID/where) , or even why that specific process can't move to another node (/proc/$PID/cantmove) , how many times it migrated (/proc/$PID/migrate)

As we will see later there are also graphical user interfaces to see or modify these values, but in a scripted environment these may come in handy !