Hi all, thanks for all the answers so far, it turns out that it actually isn't that much of a problem: I just had some inconsistencies in my input, which made giraph explode. I did a rerun with correct input data and now the whole thing finishes in a few seconds.
It would of course be nice to have the described out-of-process messaging with spill over to disk for bigger problems, but that seems to be not necessary for the problem space I am in right now :-). --André
