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https://issues.apache.org/jira/browse/CURATOR-570?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17129402#comment-17129402
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Rhys Yarranton commented on CURATOR-570:
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Getting confused here. ZooKeeper does not give Curator a connection string.
It supplies a node of configuration information. Curator reads this and
constructs a connection string from it.
If you're using Exhibitor, then it's different, and ExhibitorEnsembleProvider
does a lot of work checking for updates _etc._ But if using ZooKeeper's
dynamic reconfiguration, the FixedEnsembleProvider is essentially just a holder
for the connection string. The logic to decide when new connection strings are
required and how to construct them lies elsewhere.
> Excessive calls to ZooKeeper.updateServerList (which can result in session
> death)
> ---------------------------------------------------------------------------------
>
> Key: CURATOR-570
> URL: https://issues.apache.org/jira/browse/CURATOR-570
> Project: Apache Curator
> Issue Type: Bug
> Components: Framework
> Affects Versions: 4.2.0, 4.3.0
> Reporter: Rhys Yarranton
> Priority: Major
>
> On suspend and reconnect, Curator calls ZooKeeper.updateServerList via
> ConnectionState.checkState --> ConnectionState.handleNewConnectionString. In
> addition, recipes may be triggered by this as well, and they too make calls
> ZooKeeper.updateServerList via ConnectState.checkTimeouts -->
> ConnectionState.handleNewConnectionString.
> This happens even though the connection string has not actually changed.
> Due to ZOOKEEPER-3825, this can cause the connection to be closed
> immediately. On its own this would be perceived as a glitch. But due to the
> Curator-induced calls, what we see is a cycle of SUSPENDED/RECONNECTED, until
> eventually the session dies and a new session is recreated.
> Based on the source code (at time of writing), ZooKeeper.updateServerList is
> not intended to be called frequently like this.
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