Yann Lesage at synectique tried to do external storage of moose models.
He spent a lot of time on it, did several experiments.
MongoDB was not the solution he chose in the end (cyril told yesterday
me what it was but I already forgot :-) )
It was still very slow when he left the company (prior to it going
bankrupt) and speedup was involving analyses to try to reduce the
number of request to the DB.
Bottom line is: do you have months of full time development to put in
RMod team -- Inria Lille