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hadoopcluster-computingadministration

Hadoop Administration

I setup a Hadoop 1.2.x version, Two node Cluster. First Node (NameNode, Jobtracker) and Second Node (Secondary NameNode, Datanode, TaskTracker).

How do I Set the map and reduce slots to 4 and 2 respectively for each node and How do I verify the same from command line.

Solution

  • To set the slots per tasktracker node, limit the maximum number of tasks a node can run simultaneously.

    Add these properties to mapred-site.xml

    <property>
   <name>mapred.tasktracker.map.tasks.maximum</name>
   <value>4</value>
</property>
<property>
   <name>mapred.tasktracker.reduce.tasks.maximum</name>
   <value>2</value>
</property>

    You can check the configurations used by jobtracker using 

    hadoop jobtracker -dumpConfiguration