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https://issues.apache.org/jira/browse/HDFS-7991?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14388796#comment-14388796
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Allen Wittenauer edited comment on HDFS-7991 at 3/31/15 4:31 PM:
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bq. (since the stop command only waits 5s)
This is easily fixed by just increasing the timeout or adding logic other logic
such as asking if the NN is still alive, etc.
But in any case, it occurred to me this morning that the current code just flat
out won't work in practice. The problem is that HADOOP_OPTS has the NN's
configuration inside it. So, for example, if a user sets the heap size to 64g,
then dfsadmin is going to run with a 64g heap as well. Same thing with gc logs
and any other custom JVM setting.
The code absolutely must shell out another bin/hdfs process to get the proper
HADOOP_OPTS setting. I suspect it will actually have to use a subshell plus
parameter captures so that the environment is clean due to various {{export}}
statements throughout the code and in a lot of user's *-env.sh files.
was (Author: aw):
bq. (since the stop command only waits 5s)
This is easily fixed by just increasing the timeout or adding logic other logic
such as asking if the NN is still alive, etc.
But in any case, it occurred to me this morning that the current code just flat
out won't work in practice. The problem is that HADOOP_OPTS has the NN's
configuration inside it. So, for example, if a user sets the heap size to 64g,
then dfsadmin is going to run with a 64g heap as well. Same thing with gc logs
and any other custom JVM setting.
The code absolutely must shell out another bin/hdfs process to get the proper
HADOOP_OPTS setting. I suspect it will actually have to use a subshell plus
captures parameters so that the environment is clean due to various {{export}}
statements throughout the code and in a lot of user's *-env.sh files.
> Allow users to skip checkpoint when stopping NameNode
> -----------------------------------------------------
>
> Key: HDFS-7991
> URL: https://issues.apache.org/jira/browse/HDFS-7991
> Project: Hadoop HDFS
> Issue Type: Improvement
> Affects Versions: 3.0.0
> Reporter: Jing Zhao
> Assignee: Jing Zhao
> Attachments: HDFS-7991.000.patch, HDFS-7991.001.patch,
> HDFS-7991.002.patch, HDFS-7991.003.patch
>
>
> This is a follow-up jira of HDFS-6353. HDFS-6353 adds the functionality to
> check if saving namespace is necessary before stopping namenode. As [~kihwal]
> pointed out in this
> [comment|https://issues.apache.org/jira/browse/HDFS-6353?focusedCommentId=14380898&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14380898],
> in a secured cluster this new functionality requires the user to be kinit'ed.
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