Hadoop Administration

1
votes

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.

1
hadoopcluster-computingadministration

1 Answers

1
votes

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