[
https://issues.apache.org/jira/browse/HBASE-14891?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15029529#comment-15029529
]
Yu Li commented on HBASE-14891:
-------------------------------
Thanks for the note [~chenheng], it's by purpose to show the change more
clearly. Let me upload another one following code format. :-)
> Add log for uncaught exception in RegionServerMetricsWrapperRunnable
> --------------------------------------------------------------------
>
> Key: HBASE-14891
> URL: https://issues.apache.org/jira/browse/HBASE-14891
> Project: HBase
> Issue Type: Improvement
> Components: metrics
> Reporter: Yu Li
> Assignee: Yu Li
> Priority: Minor
> Attachments: HBASE-14891.patch
>
>
> We are using ScheduledExecutorService#scheduleWithFixedDelay to periodically
> reporting metrics. From javadoc of this method
> {quote}
> If any execution of the task encounters an exception, subsequent executions
> are suppressed.
> {quote}
> We could see if any uncaught exception like NPE thrown in the task thread,
> there won't be any error thrown but the task would be silently terminated.
> In our real case we were making some modification to the metrics and causing
> NPE carelessly, then we found metrics disappeared but cannot get a clue from
> RS log.
> Suggest to catch Throwable in
> MetricsRegionServerWrapperImpl$RegionServerMetricsWrapperRunnable, add some
> log there and suppress the exception to give it another try at next scheduled
> run.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
