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  1. Hadoop HDFS
  2. HDFS-7255

Customize Java Heap min/max settings for individual processes

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    • Tags:
      namenode datanode zkfc journalnode java heap min max

      Description

      The NameNode and JournalNode (and ZKFC) can all run on the same machine. However, they get their heap settings from HADOOP_HEAPSIZE/JAVA_HEAP_MAX. There are scenarios where the NameNode process should have different Java memory requirements than the JournalNode and ZKFC (e.g. if the machine has 10 GB of RAM, and I want the NameNode process to have 8 GB max).

      HADOOP_(.*)_OPTS variables exist for these processes and can be used to add the Xms and Xmx tags, but because of how the default for JAVA_HEAP_MAX is set, it will always add '-Xmx1000m' to the final call to start up the NameNode/JournalNode/ZKFC process, resulting in two different Java heap settings (e.g. -Xmx1000m and -Xmx8g is used when starting the NameNode).

      Note: HADOOP_HEAPSIZE is deprecated according to HADOOP-10950

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            • Assignee:
              Unassigned
              Reporter:
              neverendingqs Mark Tse
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              • Created:
                Updated: