Running matlab in the background

Question

Hi,

I am running matlab on 48 virtual machines and would like to automate it. I ssh into the machines then use matlab -r matlab_command > outfile.txt & to get the process to run in the background and run fine when I logout. The only problem is that when i jobs my process is stopped and won't start until I fg ^z bg. Is there a matlab flag so that I can run it in the background without having it stop?

Thanks, Mike

For clarification this is the order of commands that don't work

ssh server

matlab -r matlab_command > outfile.txt &

jobs

[1] Stopped

To fix this I

fg

^z

bg

logout

and it now works

Answer 1

Use nohup command on UNIX to prevent MATLAB stop when you logout.

nohup matlab -nodisplay -nosplash -r matlab_command > outfile.txt &

And don't foret to include exit; at the end of matlab_command script.

UPDATE:

Try this solution: Is it possible to run MATLAB in the background under UNIX?

There is an explanation here.

Answer 2

The real clean solution to your problem is to use GNU Screen. Then you will not loose your Matlab session and you can always get back into the Matlab prompt. Very helpful if somebody went wrong with your Matlab code and you need to debug a little.

Just fire up 'screen' (after you have the package installed, included in all major distributions). You will have a typical prompt, but inside a persistent, virtual terminal. Start your matlab as usual, omit any backgrounding. Then press CTRL+A, D (first CTRL+A, then d). You will be out of screen. You can logout. If you want to get back to your screen session, run screen -r. If you want, you can also directly start screen matlab [...] in the first place. It will have the effect that your virtual session is also dropped when matlab quits.