[
https://issues.apache.org/jira/browse/HADOOP-18038?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Mariusz Okulanis updated HADOOP-18038:
--------------------------------------
Affects Version/s: 3.2.2
(was: 3.3.2)
> "hdfs --daemon start" command may write invalid PID to file
> -----------------------------------------------------------
>
> Key: HADOOP-18038
> URL: https://issues.apache.org/jira/browse/HADOOP-18038
> Project: Hadoop Common
> Issue Type: Bug
> Components: scripts
> Affects Versions: 3.2.2
> Reporter: Mariusz Okulanis
> Priority: Minor
>
> Starting a daemon with hdfs --daemon start ... (and also yarn --daemon start
> ...) might result in writing invalid PID to PIDfile.
> Root cause of the issue is a fact that both daemon launching bash functions -
> hadoop_start_daemon and hadoop_start_daemon_wrapper - are concurrently
> writing different PIDs to the same file, and only PID written by
> hadoop_start_daemon_wrapper is correct. Order of those writes is weakly
> synchronised (with hardcoded 5s timeout). Under specific circumstances (like
> heavy CPU load) this ordering might not be preserved resulting in invalid PID
> ending up in PIDfile.
>
> Possible solution: It seems that it's unnecessary for hadoop_start_daemon to
> write to pidfile if it's being called from hadoop_start_daemon_wrapper - it
> should skip this step in this scenario.
--
This message was sent by Atlassian Jira
(v8.20.1#820001)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
