[Beowulf] size of swap partition

[Mikhail Kuzminsky]

A lot of time ago it was formulated simple rule for swap partition 
size
(equal to main memory size).

Currently we all have relative large RAM on the nodes (typically, I 
beleive, it is 2 or more GB per core; we have 16 GB per dual-socket 
quad-core Opteron node). What is typical modern swap size today?

I understand that it depends from applications ;-) We, in particular, 
practically don't have jobs which run "out-of-RAM". For single core 
dual-socket Opteron nodes w/4GB RAM per node and "molecular modelling 
workload" we used 4 GB swap partition.

But what are the reccomendations of modern praxis ?

Mikhail Kuzminksy
Computer Assistance to Chemical Research Center
Zelinsky Inst. of Organic Chemistry
Moscow