Varad, Looking at the code for the PiEstimator class which implements the 'pi' example, the two arguments are mandatory and are used *before* the job is submitted for execution - i.e on the client side. In particular, one of them (nSamples) is used not by the MapReduce job, but by the client code (i.e. PiEstimator) to generate some input.
Hence, I believe all of this additional work that is being done by the PiEstimator class will be bypassed if we directly use the job -submit command. In other words, I don't think these two ways of running the job: - using the "hadoop jar examples pi" - using hadoop job -submit are equivalent. As a general answer to your question though, if additional parameters are used by the Mappers or reducers, then they will generally be set as additional job specific configuration items. So, one way of using them with the job -submit command will be to find out the specific names of the configuration items (from code, or some other documentation), and include them in the job.xml used when submitting the job. Thanks Hemanth On Sun, Sep 23, 2012 at 1:24 PM, Varad Meru <meru.va...@gmail.com> wrote: > Hi, > > I want to run the PiEstimator example from using the following command > > $hadoop job -submit pieestimatorconf.xml > > which contains all the info required by hadoop to run the job. E.g. the > input file location, the output file location and other details. > > <property><name>mapred.jar</name><value>file:////Users/varadmeru/Work/Hadoop/hadoop-examples-1.0.3.jar</value></property> > <property><name>mapred.map.tasks</name><value>20</value></property> > <property><name>mapred.reduce.tasks</name><value>2</value></property> > ... > <property><name>mapred.job.name</name><value>PiEstimator</value></property> > <property><name>mapred.output.dir</name><value>file:////Users/varadmeru/Work/out</value></property> > > Now, as we now, to run the PiEstimator, we can use the following command too > > $hadoop jar hadoop-examples.1.0.3 pi 5 10 > > where 5 and 10 are the arguments to the main class of the PiEstimator. How > can I pass the same arguments (5 and 10) using the job -submit command > through conf. file or any other way, without changing the code of the > examples to reflect the use of environment variables. > > Thanks in advance, > Varad > > ----------------- > Varad Meru > Software Engineer, > Business Intelligence and Analytics, > Persistent Systems and Solutions Ltd., > Pune, India.
