java - Mapreduce tasks not running in parallel in pseudodistributed hadoop -

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i using hadoop on single node cluster in pseudodistributed mode. system has 16 cores, hadoop runs 1 map or reduce task @ time, not utilizing cores. changed conf/mapred-site.xml following still doesn't work. can tell me can problem , solution.

<configuration>      <property>         <name>mapred.job.tracker</name>         <value>localhost:9001</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>      <property>         <name>mapred.map.tasks</name>         <value>4</value>     </property>      <property>         <name>mapred.reduce.tasks</name>         <value>4</value>     </property>  </configuration>

if file size analyzing less block size (dfs.blocksize in hdfs-default.xml) file not splited , 1 map task run, despite of number of mappers have configured. try analyzing bigger files or reducing block size; several splits created, same amount of mappers.


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