[jira] [Updated] (HADOOP-12855) Add option to disable JVMPauseMonitor across services

["John Zhuge (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/HADOOP-12855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

John Zhuge updated HADOOP-12855:
--------------------------------
    Attachment: HADOOP-12855-001.patch

Patch 001:
* Start a pause monitor thread only when no such thread is running in JVM
* Stop the thread when stopping the last instance of JvmPauseMonitor
* Pass TestMiniDFSCluster and TestMiniYarnCluster unit tests. Only see 1 line of log message “Starting JVM pause monitor" per minicluster session.

> Add option to disable JVMPauseMonitor across services
> -----------------------------------------------------
>
>                 Key: HADOOP-12855
>                 URL: https://issues.apache.org/jira/browse/HADOOP-12855
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: performance
>    Affects Versions: 2.8.0
>         Environment: JVMs with miniHDFS and miniYarn clusters
>            Reporter: Steve Loughran
>            Assignee: John Zhuge
>         Attachments: HADOOP-12855-001.patch
>
>
> Now that the YARN and HDFS services automatically start a JVM pause monitor, if you start up the mini HDFS and YARN clusters, with history server, you are spinning off 5 + threads, all looking for JVM pauses, all printing things out when it happens.
> We do not need these monitors in minicluster testing; they merely add load and noise to tests.
> Rather than retrofit new options everywhere, how about having a "jvm.pause.monitor.enabled" flag (default true), which, when set, starts off the monitor thread.
> That way, the existing code is unchanged, there is always a JVM pause monitor for the various services —it just isn't spinning up threads.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)