On Ubuntu 11.04, /proc/[pid] contains oom_score_adj, but man proc describes the old oom_adj.
What I need to arrange is that processes started by 'pbs' or 'gridengine' are killed before anything else gets killed. Can anyone propose an easier scheme than a script that acquires the pid of the executor daemon and sticks a suitable value into the /proc/[pid] value.
A process's oom_score_adj is inherited from its parent process. Adjust it from the executor daemon (if it it's started by an init script, that would be a great place to do it) and all of the jobs it starts will have the adjusted value.
A description of what oom_score_adj does can be found on LWN.