[jira] [Commented] (HADOOP-10245) Hadoop command line always appends "-Xmx" option twice

["Wei Yan (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HADOOP-10245?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13877002#comment-13877002 ] 

Wei Yan commented on HADOOP-10245:
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Hey, shanyu. Is this one related to HADOOP-9870?

> Hadoop command line always appends "-Xmx" option twice
> ------------------------------------------------------
>
>                 Key: HADOOP-10245
>                 URL: https://issues.apache.org/jira/browse/HADOOP-10245
>             Project: Hadoop Common
>          Issue Type: Bug
>          Components: bin
>    Affects Versions: 2.2.0
>            Reporter: shanyu zhao
>            Assignee: shanyu zhao
>         Attachments: HADOOP-10245.patch
>
>
> The Hadoop command line scripts (hadoop.sh or hadoop.cmd) will call java with "-Xmx" options twice. The impact is that any user defined HADOOP_HEAP_SIZE env variable will take no effect because it is overwritten by the second "-Xmx" option.
> For example, here is the java cmd generated for command "hadoop fs -ls /", Notice that there are two "-Xmx" options: "-Xmx1000m" and "-Xmx512m" in the command line:
> java -Xmx1000m  -Dhadoop.log.dir=C:\tmp\logs -Dhadoop.log.file=hadoop.log -Dhadoop.root.logger=INFO,c
> onsole,DRFA -Xmx512m  -Dhadoop.security.logger=INFO,RFAS -classpath XXX org.apache.hadoop.fs.FsShell -ls /
> Here is the root cause:
> The call flow is: hadoop.sh calls hadoop_config.sh, which in turn calls hadoop-env.sh. 
> In hadoop.sh, the command line is generated by the following pseudo code:
> java $JAVA_HEAP_MAX $HADOOP_CLIENT_OPTS -classpath ...
> In hadoop-config.sh, $JAVA_HEAP_MAX is initialized as "-Xmx1000m" if user didn't set $HADOOP_HEAP_SIZE env variable.
> In hadoop-env.sh, $HADOOP_CLIENT_OPTS is set as this:
> export HADOOP_CLIENT_OPTS="-Xmx512m $HADOOP_CLIENT_OPTS"
> To fix this problem, we should remove the "-Xmx512m" from HADOOP_CLIENT_OPTS. If we really want to change the memory settings we need to use $HADOOP_HEAP_SIZE env variable.



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