javahadoopconfigurationhadoop-yarnkylin

Update to mapred-default.xml not visible in web UI configuration


I have an Apache Kylin container running in docker. I was getting a Java heap space error in map reduce phase so I tried updating some parameters in Hadoop mapred-default.xml file. After making the changes, I restarted the container but, when I go to Yarn ResourceManager Web UI and then to Configuration:

Yarn ResourceManager Web UI screenshot

An xml file is opened, looking like this:

enter image description here

However my new values for the properties that I set inside the mapred-default.xml are not here, it is showing the old values for those properties... Does anyone have any idea why that is happening and what I should do to make it register the new values? I tried restarting the container, but it didn't help...


Solution

  • To override a default value for a property, specify the new value within the tags, inside mapred-site.xml not mapred-default.xml, using the following format:

    <property>
     <name>mapreduce.map.memory.mb</name>
     <value>1024</value>
    </property>
    

    Be sure restart yarn after reconfigure by stop-yarn.sh and start-yarn.sh.