Mark Tse created HDFS-7255: ------------------------------ Summary: Customize Java Heap min/max settings for individual processes Key: HDFS-7255 URL: https://issues.apache.org/jira/browse/HDFS-7255 Project: Hadoop HDFS Issue Type: Improvement Components: datanode, journal-node, namenode Affects Versions: 2.5.1, 2.4.1 Reporter: Mark Tse
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] -- This message was sent by Atlassian JIRA (v6.3.4#6332)