How to setup and interactive job on abel

In order to run an interactive job on abel it is good to first start the little linux program screen. After starting screen we start-up a qlogin to request computing time.

Steps to run an interactive job on abel

• start a screen(see below on how to do that)
• Next ask for a qlogin, for instance:

  qlogin --account=nn9305k --mem-per-cpu=3800M --cpus-per-task=4
   --time=10:0:0
  

• once the job is accepted sourceit to active it

  source /cluster/bin/jobsetup
  

• now you can load module, run programs etc…
• if you need to detach (you might want to go home, but the program is still busy) then do:

  ctrl-a d
  

• reattach by using the command: screen -r
• if the program is done that use the command exitto stop the qlogin and then again exit to deactivate the screen.

A few basic commands for using screen:

To start a screen type on the commandline:

screen

detaching from a running screen:

ctrl-a d

re-attaching to a running screen:

screen -r

check if there are screens running

screen -ls

this might give you an output that looks a bit like this:

There are screens on:
        2477.pts-0.server1      (Detached)
        2522.pts-0.server1      (Detached)
2 Sockets in /var/run/screen/S-root.

then re-attach using the command:

screen -r 2477.pts-0.server1

and finally stop a running screen by typing:

exit

Here is a nice tutorial on using screen.