With 100,000 points as both demand and facility, and no spatial (distance/time) constraints, the process will likely run out of memory trying to compute/store the OD matrix with ten billion entries. I would suggest that you intelligently cut down on your facilities so that not all 100,000 are used. One way is to randomly select a smaller set, say 1000 facilities, using the "Create Random Points" GP tool. BTW, if you gave it 100,000 facilities and had a reasonable distance cutoff so that a full matrix is not computed, the 100,000 choose a few facilities is still a very large number of combinations to evaluate and get an answer in reasonable time. I strongly suggest not having more than a 1000 facilities with 100000 demand points, and still do add a distance cutoff.
Jay Sandhu