This is a very subtle bug.  GiraphJob inherits from
org.apache.mapreduce.Job.  However, the methods submit() and
waitForCompletion() are not overridden.  I assumed that they were
implemented, so when I called either one of these methods, the framework
started up identity mappers/reducers.  A simple fix is to throw
unsupported operation exceptions or to implement these methods.  Perhaps
this has been done already?


On 2/7/12 7:46 PM, "David Garcia" <> wrote:

>I am running into a weird error that I haven't seen yet (I suppose I've
>been lucky).  I see the following in the logging:
>org.apache.hadoop.util.NativeCodeLoader: Unable to load native-hadoop
>library for your platform... using builtin-java classes where applicable
>In the job definition, the property "" is not even
>defined.  For Giraph, this is usually set to
>I'm building my project with hadoop 0.20.204.
>When I build the GiraphProject myself (and run my own tests with the
>projects dependencies), I have no problems.  The main difference is that
>I'm using a Giraph dependency in my work project.  All input is welcome.

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