I want to change policy of scheduling in Hadoop, how to I can change job order in map reduce automatically.
Assume you are using Hadoop 2 / YARN.
The configuration parameter named
yarn.resourcemanager.scheduler.class controls the class to be used as the resource scheduler for YARN/Hadoop.
The default value for the scheduler class (check more at http://ask.systutorials.com/749/hadoop-2-yarn-default-configuration-values) is:
which is the Capacity Scheduler.
To change the scheduler used, you need to assign the scheduler class in yarn-site.xml in the etc/hadoop/ directory under Hadoop installation. Taking the fair scheduler shipped with Hadoop as an example, we can add to yarn-site.xml:
<property> <name>yarn.resourcemanager.scheduler.class</name> <value>org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.FairScheduler</value> </property>