Progressable exception can be caused by many different reasons (it's totally unrelated to aggregators), and when looking at which exception it's caused by users should get better sense about what's going on. What you are suggesting about providing default master compute is not doable, since the part which needs to be done there is aggregator registration. We can't know what kind of aggregators (names and types) an application needs. I remember I was talking about writing a short tutorial for aggregators long time ago, sorry for not doing that, will try to get to it soon.
From: Eli Reisman <[email protected]<mailto:[email protected]>> Reply-To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Date: Thursday, February 14, 2013 2:23 PM To: "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Subject: Re: InputFormat for the example SimpleMasterComputeVertex Other folks on the list are also having this problem with the progressable utile exception & job failures. I don't know much about master compute usage but if it is needed to make the aggregators work, maybe we should have a default dummy class that just handles aggregators if no other master compute is specified? Or a wiki page? The progressable error message does not lead us to this conclusion directly. On Wed, Feb 13, 2013 at 3:04 AM, Maria Stylianou <[email protected]<mailto:[email protected]>> wrote: Hey, I am trying to run the example SimpleMasterComputeVertex, but no matter which Input Format and graph I give, it doesn't work. Each worker gives the error: Caused by: java.lang.NullPointerException at org.apache.giraph.examples.SimpleMasterComputeVertex.compute(SimpleMasterComputeVertex.java:42) This line 42 is the first line of the compute() public void compute(Iterable<DoubleWritable> messages){ So I guess, the initialization is not done correctly, because the input file does not have the correct format. Any help would be appreciated, Thanks! Maria -- Maria Stylianou Intern at Telefonica, Barcelona, Spain Master Student of European Master in Distributed Computing<http://www.kth.se/en/studies/programmes/master/em/emdc> Universitat Politècnica de Catalunya - BarcelonaTech, Barcelona, Spain KTH Royal Institute of Technology, Stockholm, Sweden
