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From Pavan Kumar A <>
Subject RE: receiving messages that I didn't send
Date Tue, 23 Sep 2014 15:46:00 GMT
Can you give more context?What are the types of messages, patch of your compute method, etc.You
will not receive messages that are not sent, but one thing that can happen is-- message can
have multiple parameters.suppose message objects can have 2 parametersm - a,bsay in m's write(out)
you do not handle the case of b = nullm1 sets bm2 has b=nullthen because of incorrect code
for m's write() m2 can show b = m1.bthat is because message objects will be re-used when receiving.
This is a Giraph gotcha, because ofobject reuse in most iterators.

> From:
> Date: Tue, 23 Sep 2014 10:10:48 -0400
> Subject: receiving messages that I didn't send
> To:
> Hi Folks. I am refactoring my compute()  to use a set of ids as its
> message type, and in my tests it is receiving a message that it
> absolutely did not send. I've debugged it and am at a loss.
> Interestingly, I encountered this once before and solved it by
> creating a copy of a Writeable instead of re-using it, but I haven't
> been able to solve it this time. In general, does this anomalous
> behavior indicate a Giraph/Hadoop gotcha'? It's really confounding!
> Thank very much -- matt
> -- 
> Matthew Cornell | | 413-626-3621 | 34
> Dickinson Street, Amherst MA 01002 |
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