hadoop-yarn-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Paul Rogers (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (YARN-3066) Hadoop leaves orphaned tasks running after job is killed
Date Tue, 03 May 2016 02:39:12 GMT

    [ https://issues.apache.org/jira/browse/YARN-3066?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15267966#comment-15267966

Paul Rogers commented on YARN-3066:

This problem persists on Mac OS El Capitan. However, a workaround exists in the form of this
simple Git project: https://github.com/jerrykuch/ersatz-setsid.

* Install the Apple XCode command line tools.
* Clone the project.
* Build the project using make.
cd ersatz-setsid
* Copy the resulting setsid program to /usr/bin:
sudo cp setsid /usr/bin
* Restart YARN.

Now, your process will shut down correctly.

YARN already has included C code. YARN could save us all a ton of grief (took me a day to
track down this issue to find this bug) by including it's own version of setsid.

> Hadoop leaves orphaned tasks running after job is killed
> --------------------------------------------------------
>                 Key: YARN-3066
>                 URL: https://issues.apache.org/jira/browse/YARN-3066
>             Project: Hadoop YARN
>          Issue Type: Bug
>          Components: nodemanager
>         Environment: Hadoop 2.4.1 (probably all later too), FreeBSD-10.1
>            Reporter: Dmitry Sivachenko
> When spawning user task, node manager checks for setsid(1) utility and spawns task program
via it. See hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/DefaultContainerExecutor.java
for instance:
> String exec = Shell.isSetsidAvailable? "exec setsid" : "exec";
> FreeBSD, unlike Linux, does not have setsid(1) utility.  So plain "exec" is used to spawn
user task.  If that task spawns other external programs (this is common case if a task program
is a shell script) and user kills job via mapred job -kill <Job>, these child processes
remain running.
> 1) Why do you silently ignore the absence of setsid(1) and spawn task process via exec:
this is the guarantee to have orphaned processes when job is prematurely killed.
> 2) FreeBSD has a replacement third-party program called ssid (which does almost the same
as Linux's setsid).  It would be nice to detect which binary is present during configure stage
and put @SETSID@ macros into java file to use the correct name.
> I propose to make Shell.isSetsidAvailable test more strict and fail to start if it is
not found:  at least we will know about the problem at start rather than guess why there are
orphaned tasks running forever.

This message was sent by Atlassian JIRA

To unsubscribe, e-mail: yarn-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: yarn-issues-help@hadoop.apache.org

View raw message