Thanks a lot, Benjamin.

I set the number of maptask as 2 since I only have a duo-core processor
(though with hyperthread) on my laptop. I ran it again but it still
appeared incorrect. The output is as follows.

Regards,
Robert

$ hadoop jar target/giraph-0.2-SNAPSHOT-jar-with-dependencies.jar
org.apache.giraph.benchmark.PageRankBenchmark -e 1 -s 3 -v -V 50000000 -w 2
12/03/31 11:40:08 INFO benchmark.PageRankBenchmark: Using class
org.apache.giraph.benchmark.HashMapVertexPageRankBenchmark
12/03/31 11:40:10 WARN bsp.BspOutputFormat: checkOutputSpecs:
ImmutableOutputCommiter will not check anything
12/03/31 11:40:11 INFO mapred.JobClient: Running job: job_201203301834_0004
12/03/31 11:40:12 INFO mapred.JobClient:  map 0% reduce 0%
12/03/31 11:40:38 INFO mapred.JobClient:  map 33% reduce 0%
12/03/31 11:45:44 INFO mapred.JobClient: Job complete: job_201203301834_0004
12/03/31 11:45:44 INFO mapred.JobClient: Counters: 5
12/03/31 11:45:44 INFO mapred.JobClient:   Job Counters
12/03/31 11:45:44 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=620769
12/03/31 11:45:44 INFO mapred.JobClient:     Total time spent by all
reduces waiting after reserving slots (ms)=0
12/03/31 11:45:44 INFO mapred.JobClient:     Total time spent by all maps
waiting after reserving slots (ms)=0
12/03/31 11:45:44 INFO mapred.JobClient:     Launched map tasks=2
12/03/31 11:45:44 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=4377

On Sat, Mar 31, 2012 at 3:45 AM, Benjamin Heitmann <
benjamin.heitm...@deri.org> wrote:

>
> Hi Robert,
>
> On 31 Mar 2012, at 09:42, Robert Davis wrote:
>
> > Hello Giraphers,
> >
> > I am new to Giraph. I just check out a version and ran it in the single
> > machine mode. I got the following results which has no Giraph counter
> > information (as those in the example output). I am wondering what has
> gone
> > wrong. The hadoop I am using is 1.0
>
> it looks like your Giraph job did not actually finish the calculation.
>
> As you say that you are new to Giraph, there might be a high chance that
> you ran into the same issue which tripped me up a few weeks ago ;)
>
> (I am not sure where the following information should be documented,
> maybe this issue should be documented on the same page which describes how
> to run the pagerank benchmark)
>
> You provide the parameter "-w 30" to your job, which means that it will
> use 30 workers. Maybe thats from the example on the Giraph web page,
> however there is one very important caveat for the number of workers:
> the number of workers needs to be smaller then
> mapred.tasktracker.map.tasks.maximum minus one.
>
> Giraph will use one mapper task to start some sort of coordinating worker
> (probably something zookeeper specific),
> and then it will start the number of workers which you specified using -w
> . If the total number of workers is bigger then the maximum number of tasks,
> then your Giraph job will not finish actually calculating stuff.
> (There might be a config option for specifying how many workers need to be
> finished in order to start the next superstep,
> but I did not try that personally.)
>
> If you are running Hadoop/Giraph on your personal machine, then I would
> recommend, using 3 workers, and you should edit your conf/mapred-site.xml
> to include some values for the following configuration parameters (and
> restart hadoop...)
>
>  <property>
>    <name>mapred.map.tasks</name>
>    <value>4</value>
>  </property>
>  <property>
>    <name>mapred.reduce.tasks</name>
>    <value>4</value>
>  </property>
>  <property>
>    <name>mapred.tasktracker.map.tasks.maximum</name>
>    <value>4</value>
>  </property>
>  <property>
>    <name>mapred.tasktracker.reduce.tasks.maximum</name>
>    <value>4</value>
>  </property>
>
>
>

Reply via email to