Group Experimentation Support

Set up torque/PBS

This section describes how to set up torque PBS. If it's already set up, skip this section. First, we install the torque PSB system:

apt-get install torque-server torque-scheduler torque-mom torque-client

Then stop all the running torque processes:

/etc/init.d/torque-mom stop
/etc/init.d/torque-scheduler stop
/etc/init.d/torque-server stop

Create the PBS server (say "yes" when prompted):

pbs_server -t create

Then kill the PBS server process:

killall pbs_server

Set up the PBS server:

echo $(hostname -f) > /etc/torque/server_name
echo $(hostname -f) >  /var/spool/torque/server_priv/acl_svr/acl_hosts
echo $(hostname -f) > /var/spool/torque/mom_priv/config

echo root@$(hostname -f) > /var/spool/torque/server_priv/acl_svr/operators
echo root@$(hostname -f) > /var/spool/torque/server_priv/acl_svr/managers

echo "$(hostname -f) np=4" > /var/spool/torque/server_priv/nodes

If you have a line in your /etc/hosts file that resolves your hostname to 127.0.1.1, you have to comment it out, e.g.

#127.0.1.1  console.grid.orbit-lab.org  console

Once you've done that, start everything back up again:

/etc/init.d/torque-server start
/etc/init.d/torque-scheduler start
/etc/init.d/torque-mom start

Now we'll set up some configuration values:

qmgr -c "set server scheduling = True"
qmgr -c "set server acl_host_enable = True"
qmgr -c "set server acl_hosts = $(hostname -f)"
qmgr -c "set server allow_node_submit = True"

You'll have to run the commands above as root, since you've set up the root user as the only PBS operator and manager.

Set up queues

Next we'll set up queues: one for each node.

For various reasons, we've decided to make a queue per node and have the console be the single "compute" node, instead of having the nodes be the "compute" nodes. (Mainly because then we can still use legacy disk images, and don't have to worry about configuring the nodes to work with torque.) It might seem "neater" to use "nodes" instead of queues, because this would make it simpler to run an experiment with multiple nodes. In practice, though, it would still be annoying to run an experiment with multiple nodes because you generally care which nodes in this scenario (e.g. you want nodes that are close.)

First we get a list of nodes, then we'll set up a queue for each one:

list=$(omf stat -t system:topo:all | grep "Node:" | awk -F" " '{print $2}' | cut -f1 -d$'.')

for l in $list
do 
    qmgr -c "create queue $l"
    qmgr -c "set queue $l queue_type = Execution"
    qmgr -c "set queue $l max_running = 1"
    qmgr -c "set queue $l enabled = True"
    qmgr -c "set queue $l started = True"
done

(Again, this must be done as root or as a queue manager.)

Now we'll disable all the queues, because we are going to re-enable them selectively.

list=$(qstat -Q | tail -n+3 | awk -F" " '{print $1}')

for l in $list
do 
    qdisable "$l"
done

Check with

qstat -Q