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Hadoop, mail # user - passing arguments to hadoop job


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jamal sasha 2013-01-21, 23:52
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Satbeer Lamba 2013-01-22, 01:40
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jamal sasha 2013-01-22, 01:47
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Re: passing arguments to hadoop job
Hemanth Yamijala 2013-01-22, 07:58
OK. The easiest way I can think of for debugging this is to add a
System.out.println in your Reduce.configure code. The output will come in
the logs specific to your reduce tasks. You can access these logs from the
web ui of the jobtracker. Navigate to your job page from the Jobtracker UI
> reduce >  select any task > click on the task log links. Look under
'stdout'.

Thanks
Hemanth
On Tue, Jan 22, 2013 at 11:19 AM, jamal sasha <[EMAIL PROTECTED]> wrote:

> Hi,
>   The driver code is actually the same as of java word count old example:
> copying from site
> public static void main(String[] args) throws Exception {
>     JobConf conf = new JobConf(WordCount.class);
>      conf.setJobName("wordcount");
>
>      conf.setOutputKeyClass(Text.class);
>      conf.setOutputValueClass(IntWritable.class);
>      * conf.setInt("basecount",200000); // added this line*
>      conf.setMapperClass(Map.class);
>      conf.setCombinerClass(Reduce.class);
>      conf.setReducerClass(Reduce.class);
>
>      conf.setInputFormat(TextInputFormat.class);
>      conf.setOutputFormat(TextOutputFormat.class);
>
>      FileInputFormat.setInputPaths(conf, new Path(args[0]));
>      FileOutputFormat.setOutputPath(conf, new Path(args[1]));
>
>      JobClient.runJob(conf);
>    }
>
>
> Reducer class
>  public static class Reduce extends MapReduceBase implements Reducer<Text,
> IntWritable, Text, IntWritable> {
>      *private static int baseSum ;*
> *      public void configure(JobConf job){*
> *      baseSum = Integer.parseInt(job.get("basecount"));*
> *      *
> *      }*
>       public void reduce(Text key, Iterator<IntWritable> values,
> OutputCollector<Text, IntWritable> output, Reporter reporter) throws
> IOException {
>          int sum =* baseSum*;
>         while (values.hasNext()) {
>            sum += values.next().get();
>         }
>          output.collect(key, new IntWritable(sum));
>       }
>      }
>
> On Mon, Jan 21, 2013 at 8:29 PM, Hemanth Yamijala <
> [EMAIL PROTECTED]> wrote:
> >
> > Hi,
> >
> > Please note that you are referring to a very old version of Hadoop. the
> current stable release is Hadoop 1.x. The API has changed in 1.x. Take a
> look at the wordcount example here:
> http://hadoop.apache.org/docs/r1.0.4/mapred_tutorial.html#Example%3A+WordCount+v2.0
> >
> > But, in principle your method should work. I wrote it using the new API
> in a similar fashion and it worked fine. Can you show the code of your
> driver program (i.e. where you have main) ?
> >
> > Thanks
> > hemanth
> >
> >
> >
> > On Tue, Jan 22, 2013 at 5:22 AM, jamal sasha <[EMAIL PROTECTED]>
> wrote:
> >>
> >> Hi,
> >>   Lets say I have the standard helloworld program
> >>
> http://hadoop.apache.org/docs/r0.17.0/mapred_tutorial.html#Example%3A+WordCount+v2.0
> >>
> >> Now, lets say, I want to start the counting not from zero but from
> 200000.
> >> So my reference line is 200000.
> >>
> >> I modified the Reduce code as following:
> >>  public static class Reduce extends MapReduceBase implements
> Reducer<Text, IntWritable, Text, IntWritable> {
> >>      private static int baseSum ;
> >>      public void configure(JobConf job){
> >>      baseSum = Integer.parseInt(job.get("basecount"));
> >>
> >>      }
> >>       public void reduce(Text key, Iterator<IntWritable> values,
> OutputCollector<Text, IntWritable> output, Reporter reporter) throws
> IOException {
> >>         int sum = baseSum;
> >>         while (values.hasNext()) {
> >>           sum += values.next().get();
> >>         }
> >>         output.collect(key, new IntWritable(sum));
> >>       }
> >>     }
> >>
> >>
> >> And in main added:
> >>    conf.setInt("basecount",200000);
> >>
> >>
> >>
> >> So my hope was this should have done the trick..
> >> But its not working. the code is running normally :(
> >> How do i resolve this?
> >> Thanks
> >
> >
>
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Mohammad Tariq 2013-01-22, 06:23