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From Claudio Martella <>
Subject Re: Are new vertices active?
Date Wed, 26 Jun 2013 17:10:42 GMT

inline are my (tentative) answers.

On Wed, Jun 26, 2013 at 6:34 PM, Christian Krause <> wrote:

> Hi,
> if I create new vertices, will they be executed in the next superstep? And
> does it make a difference whether I create them using addVertexRequest() or
> sendMessage()?

The vertex will be active. The case of a sendMessage is intuitive, because
a message wakens up a vertex.

> Another question: if I mutate the graph in superstep X and X is the last
> superstep, will the changes be executed? It is not clear to me whether the
> graph changes are executed during or before the next superstep.

I'm actually not sure about our internal implementation, somebody can shade
light on this, but I'd expect it to be running due to above (presence of
active vertices).

> And related to the last question, if I mutate the graph in superstep X,
> and I call getTotalNumVertices() in the next step, can I expect the updated
> number of vertices, or the number of vertices before the mutation?

The mutatiations are applied at the end of a superstep and are visibile in
the following one. Hence in s+1 you'd see the new number of vertices.

> Sorry for these very basic questions, but I did not find any documentation
> on these details. If this is documented somewhere, it would be helpful to
> get a link.
> Cheers,
> Christian

   Claudio Martella

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