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Allen Wittenauer commented on YARN-3066: ---------------------------------------- So yes, it's still sealed off without a contract. Meh. > 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 (v6.3.4#6332)