Here is how I think my algo works. Please tell me where I am wrong.
@Override
public void compute(Iterator<IntWritable> messages) throws IOException {
IntWritable currentMax = this.getValue();
System.err.println();
System.err.println(getSuperstepCount());
System.err.println("At node "+this.getVertexID());
IN THE 0th SUPERSTEP, ALL VERTICES SEND THEIR VALUES TO ALL NEIGHBORING
VERTICES AND RETURN.
if(getSuperstepCount() == 0L){
System.err.println("sending msg to all neighbors
..."+currentMax.toString());
sendMessageToNeighbors(currentMax);
return;
}
//FOR ALL SUBSEQUENT SUPERSTEPS, EACH VERTEX LOOKS AT ALL VALUES IT HAS
RECEIEVED AND STORES THE MAX VALUE RECEIVED IN currentMax.
while(messages.hasNext()){
IntWritable msg = messages.next();
currentMax = (msg.compareTo(currentMax) > 0)?msg:currentMax;
}
//IF THERE IS AN UPDATE IN THE CURRENT VALUE OF THE VERTEX, THAT MEANS THAT
THE VERTEX HAS NOT VOTED TO HALT SO IT SHOULD SEND MESSAGES TO ALL ITS
NEIGHBORING NODES.
if(currentMax.compareTo(getValue()) > 0){
System.err.println("updating value to ..."+currentMax.toString());
this.setValue(currentMax);
sendMessageToNeighbors(getValue());
}
else{
IF NOT IT SHOULD SEND NO MESSAGES. i.e. THE VERTEX HAS VOTED TO HALT.
System.err.println("voting to halt...");
}
System.err.println();
}
}
AT THE END I EXPECT TO SEE AN OUTPUT FILE WHICH SHOULD BE SOMETHING LIKE
THIS
A 6
B 6
C 6
D 6
But the job fails. And there are 3 output files created part-00000 which is
empty, part-00001, again empty. and part-00002 which has C 2 written in it.
--
thanks and regards,
Apurv Verma
India
On Wed, May 30, 2012 at 12:41 PM, Apurv Verma <[email protected]> wrote:
> Yes, I ran that example by copying it verbatim, it ran. Don't know why my
> MaxFindVertex is not working.
>
>
> --
> thanks and regards,
>
> Apurv Verma
> India
>
>
>
>
>
> On Wed, May 30, 2012 at 11:31 AM, Thomas Jungblut <
> [email protected]> wrote:
>
>> Oops, I have read "with aggregator" and not without. I'm sorry Apurv.
>> Do you had a look at the mindist search/connected component example in
>> example package? It does actually the same but inverted.
>>
>>
>> 2012/5/30 Apurv Verma <[email protected]>
>>
>> > Isn't an aggregator optional?
>> >
>> > --
>> > thanks and regards,
>> >
>> > Apurv Verma
>> > India
>> >
>> >
>> >
>> >
>> >
>> > On Wed, May 30, 2012 at 11:26 AM, Thomas Jungblut <
>> > [email protected]> wrote:
>> >
>> > > Hi Apurv,
>> > >
>> > > there is no aggregator defined in your code.
>> > >
>> > > 2012/5/30 Apurv Verma <[email protected]>
>> > >
>> > > > Hello,
>> > > > After several attempts I was unable to run the MaxFindVertex
>> without
>> > > using
>> > > > Aggregators.
>> > > >
>> > > > Here is the source code. http://pastebin.com/VMTXPtRR. I have
>> changed
>> > > the
>> > > > num of bsp tasks to 1,2 and 3 but still it doesn't work. The input
>> > graph
>> > > > file is very small.
>> > > > Here is the graph file. http://pastebin.com/uAJASSRi
>> > > >
>> > > > Here are the logs.
>> > > >
>> > > > These are the task logs.
>> > > >
>> > > > 1. http://pastebin.com/imMKB6Hs
>> > > > 2. http://pastebin.com/xvMZris0
>> > > > 3. http://pastebin.com/PkgMrsdx
>> > > >
>> > > >
>> > > > The bsp master log http://pastebin.com/0uQYP03B
>> > > >
>> > > >
>> > > > The groom log http://pastebin.com/GYY9sUEv
>> > > >
>> > > > Can you please let me know my mistake.
>> > > >
>> > > > --
>> > > > thanks and regards,
>> > > >
>> > > > Apurv Verma
>> > > > India
>> > > >
>> > >
>> > >
>> > >
>> > > --
>> > > Thomas Jungblut
>> > > Berlin <[email protected]>
>> > >
>> >
>>
>>
>>
>> --
>> Thomas Jungblut
>> Berlin <[email protected]>
>>
>
>
