Thanks. Actually, I like DBSCAN a lot and use it often, though I am not much familiar with it's internals. It looks like it is iterative and thus does not fit very well to a GPU. The only way I see is to pick several seed points at start...
This paper claims a "97x improvement" over traditional (non-parallelized) DBSCAN algorithms, but that's not a very helpful claim, because it does not indicate what the computational costs are as a function of, say, the number of data points or dimensions.
