Is there a systematic way of finding out how much memory is needed?

I had some related problems recently. How much memory do you have on your system? Try increasing total memory drastically?

For an 8 processor job, I use:

memory total 22 gb[/quote]

In principle I can ask for up to 12 Gb per process, but than this job will stay in the queue forever (it will saturate the nodes compeletely and will get very low priority). My objective is to allocate just enough to get it running but keep waiting time reasonable. My molecule is rather small and on 1 CPU it runs under 1 Gb of memory, but I can't understand how to estimate memory consumption in parallel mode.