hi Sebastian thnx for the answer
I was giving a look to cassovary, but I'm losing hot to integrate it with neo4j and/or hor to calculate paths with it.....Do you have any tips? Angelo 2014-03-26 11:31 GMT+01:00 Sebastian Schelter <ssc.o...@googlemail.com>: > For such a small graph, using a single machine graph processing system > makes more sense imho. Should be faster and easier to program. Google for > cassovary. > Am 26.03.2014 10:12 schrieb "Angelo Immediata" <angelo...@gmail.com>: > > Hi there >> >> In my project I have to implement a routing system with good performance; >> at the beginning this system should be able in giving routes information >> only for one italian region (Lombardia) but it could be used for the whole >> Italy (or world....) >> Let's stop to the Lombardia for now. By reading OSM files I can create my >> own graph in the best format i can use it; then I need to use Dijkstra (or >> any other algorithm) in order to propose to the user K possible paths from >> point A to point B (K becouse i need to show to the customer also the >> alternatives). I can't use Contraction Herarchy algorithm becouse I need to >> take care of external events that can modify the weights on my built graph >> and this implies that I should create the "contracted" graph once again and >> this can be a very onerous operation >> >> By my experimentations, I saw that by reading the Lombardia OSM file I >> should create a graph with around 1 million of vertexes and 6 million of >> edges and I was thinking to use Giraph to solve my issue (I saw this link >> http://giraph.apache.org/intro.html where you talked about shortestpaths >> problem >> I have a couple of question for you giraph/hadoop gurus >> >> - does it make sense to use giraph for my scenario? >> - must i respect some graph format to pass to the giraph algorithm in >> order to have K shortest paths from point A to point B? If so....which >> format should I respect? >> - what would be perfomance by using giraph? I know that Dijstra >> algorithm problem is that it is slow.....by using giraph will I be able in >> improving its performances on very large graph? >> >> I know these can seem very basic questions, but I'm pretty new to giraph >> and I'm trying to understand it >> >> Thank you >> Angelo >> >
