[
https://issues.apache.org/jira/browse/HDFS-16042?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17356468#comment-17356468
]
Jim Brennan commented on HDFS-16042:
------------------------------------
[~ahussein] I believe this was filed due to an incident where decommissions
were happening during a rolling upgrade. They were taking longer and with the
fixed rate, they were holding the namesystem lock frequently enough that it was
impacting other operations during the upgrade. [~kihwal], [~daryn] is this
correct? Seems like a reasonable change to me. I will commit if you guys are
ok with it.
> DatanodeAdminMonitor scan should be delay based
> -----------------------------------------------
>
> Key: HDFS-16042
> URL: https://issues.apache.org/jira/browse/HDFS-16042
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: datanode
> Reporter: Ahmed Hussein
> Assignee: Ahmed Hussein
> Priority: Major
> Labels: pull-request-available
> Time Spent: 20m
> Remaining Estimate: 0h
>
> In {{DatanodeAdminManager.activate()}}, the Monitor task is scheduled with a
> fixed rate, ie. the period is from start1 -> start2.
> {code:java}
> executor.scheduleAtFixedRate(monitor, intervalSecs, intervalSecs,
> TimeUnit.SECONDS);
> {code}
> According to Java API docs for {{scheduleAtFixedRate}},
> {quote}If any execution of this task takes longer than its period, then
> subsequent executions may start late, but will not concurrently
> execute.{quote}
> It should be a fixed delay so it's end1 -> start1.
>
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
