On Wed, Sep 7, 2011 at 10:43 PM, Dmitriy Ryaboy <dmit...@twitter.com> wrote:
> Something else to think about -- in some cases you may want to
> implement extreme compression of the edge list. For example, we might
> want to calculate n-th degree reach for all nodes in a graph. Given a
> graph with a few nodes with lots of incoming edges ("biebernodes", we
> call them), anything that jumps across them winds up essentially
> replicating large chunks of the graph to each node. Things like RLE
> might make sense when you are doing that sort of thing in memory and
> only have so many terabytes of that lying around.
Right, in some cases, we may want to not have edge values at all. Just
existence in the vertex's target list of a target vertex id denotes
and so "SortedMap<I, Edge<E,I>>" gets replaced with "long".