Usually you just run top and look at the top line - or the thing with the biggest 'RES' value.

What does that coorespond to w.r.t. values in ps.

I'm doing : ps -eo sz,rssize,vsize,size

Every 5 minutes (with Munin) and totalling up each of those 4, and graphing them. None of them appear to be growing. I'm only checking the db2 processes and totalling up all db2 processes in each of those 4 areas.

I'm reasonably sure it is db2 doing it. If I look at the full process list with the above, these are the only processes taking any amount of space, and this is the only thing running on this box.

But so far I think i've determined that "committed" as found in /proc does not have any equivalent value in the process list. Not that I have been able to find at least.

I suppose it could be something other than db2 since this is the only thing I'm graphing in this way. But I'm not sure what else it would be since I have a number of other equivalent machines and none of them do this.