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https://issues.apache.org/jira/browse/HADOOP-9933?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13758976#comment-13758976
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Steve Loughran commented on HADOOP-9933:
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I'm not sure (based on past experience) that restarting arbitrary services
works reliably -it often turns out that they don't ever shut down as cleanly as
they think (leaked threads, memory, file handles). Then theres the special case
of a service that failed during init/startup (which we don't treat as a unique
termination state, but we do record with the exception that triggered the
failure, so the fact a failure occurred can be inferred.
Is there a way that we could avoid this -or add some marker interface to
indicate that the service considers itself restartable, have some
activate/passivate methods that can suspend some aspects of the system?
There's always the option of having a ready-to-roll instance that is inited but
not started; you could deploy that in a new JVM and switch it on when
triggered. I'd need to think about that design a bit more though
> Augment Service model to support starting stopped services
> ----------------------------------------------------------
>
> Key: HADOOP-9933
> URL: https://issues.apache.org/jira/browse/HADOOP-9933
> Project: Hadoop Common
> Issue Type: Improvement
> Affects Versions: 2.1.0-beta
> Reporter: Karthik Kambatla
> Assignee: Karthik Kambatla
> Labels: service
>
> For ResourceManager-HA (YARN-149 and co), we would want to start/stop/start
> RM's active services as it transitions to Active/Standby/Active respectively.
> In the current service model, we can't start the services that are already
> stopped.
> Would be nice to augment this. To avoid accidental restart of stopped
> services, we can add another API: start(boolean restartIfStopped). Thoughts?
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