I don't know much about this at all, but I'll say this since it might help. How about using the cluster that you can access? Maybe Microsoft Azure platform or other? Here's a program that, acccording to them, would take weeks to calculate that graph but they can do it in seconds using Azure cluster
http://www.dotnetsolutions.ltd.uk/ev.../wikiexplorer/
Again, it just come to my mind when I saw the thread. I'm looking forward the end result