Hey, you can preprocess your data, create the vertices and store them to a file, like you would store any other Flink DataSet, e.g. with writeAsText.
Then, you can create the graph by reading 2 datasets, like this: DataSet<Vertex> vertices = env.readTextFile("/path/to/vertices/")... // or your custom reading logic DataSet<Edge> edges = ... Graph graph = Graph.fromDataSet(vertices, edges, env); Is this what you're looking for? Also, note that if you have a very large graph, you should avoid using collect() and fromCollection(). -Vasia. On 25 November 2015 at 18:03, Stefanos Antaris <antaris.stefa...@gmail.com> wrote: > Hi Vasia, > > my graph object is the following: > > Graph<MyPojoNode, NullValue, Integer> graph = Graph.fromCollection( > edgeList.collect(), env); > > The vertex is a POJO not the value. So the problem is how could i store > and retrieve the vertex list? > > Thanks, > Stefanos > > On 25 Nov 2015, at 18:16, Vasiliki Kalavri <vasilikikala...@gmail.com> > wrote: > > Hi Stefane, > > let me know if I understand the problem correctly. The vertex values are > POJOs that you're somehow inferring from the edge list and this value > creation is what takes a lot of time? Since a graph is just a set of 2 > datasets (vertices and edges), you could store the values to disk and have > a custom input format to read them into datasets. Would that work for you? > > -Vasia. > > On 25 November 2015 at 15:09, Stefanos Antaris <antaris.stefa...@gmail.com > > wrote: > >> Hi to all, >> >> i am working on a project with Gelly and i need to create a graph with >> billions of nodes. Although i have the edge list, the node in the Graph >> needs to be a POJO object, the construction of which takes long time in >> order to finally create the final graph. Is it possible to store the Graph >> object as a file and retrieve it whenever i want to run an experiment? >> >> Thanks, >> Stefanos > > > >