-Xmx passed twice on command line

Nobody has claimed this yet.

-Xmx1000m and -Xmx512m are passed twice, likely due to scripting logic errors in hadoop-env.sh (512m is set via HADOOP_CLIENT_OPS). This isn't a big deal, but would be nice to clean up.

> achutest 60276 2.5 0.0 2732480 264768 ? Sl 11:04 0:14
> | \_ /usr/lib/jvm/jre-1.8.0/bin/java -Xmx1000m
> -Djava.net.preferIPv4Stack=true
> -Djava.io.tmpdir=/tmp/achutest/hadoop/testlsf/28794/scratch/tmp
> -Dhadoop.log.dir=/tmp/achutest/hadoop/testlsf/28794/log
> -Dhadoop.log.file=hadoop.log
> -Dhadoop.home.dir=/g/g0/achutest/bigdata/hadoop-2.7.3
> -Dhadoop.id.str=achutest -Dhadoop.root.logger=INFO,console
> -Djava.library.path=/g/g0/achutest/bigdata/hadoop-2.7.3/lib/native
> -Dhadoop.policy.file=hadoop-policy.xml -Djava.net.preferIPv4Stack=true
> -Xmx512m -Dhadoop.security.logger=INFO,NullAppender
> org.apache.hadoop.util.RunJar
> share/hadoop/mapreduce/hadoop-mapreduce-examples-2.7.3.jar teragen
> -Dmapreduce.job.maps=288 -Ddfs.datanode.drop.cache.behind.reads=true
> -Ddfs.datanode.drop.cache.behind.writes=true 10000000000
> terasort-teragen

Inspect hadoop-env.sh and the handling of HADOOP_CLIENT_OPS, then trace how JVM options are assembled for the Hadoop command shown in the report. Done means the generated command line contains only one -Xmx setting when these values are configured.

Written by the indexing model from the issue text.