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https://issues.apache.org/jira/browse/MESOS-7688?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16068755#comment-16068755
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Yan Xu commented on MESOS-7688:
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[~dzhuk] sorry I missed this reply. yes it's ~1.3.0 (hence with /r/58355/) and 
we are using the default {{--registration_backoff_factor}}, yeah we can tweak 
this number but hopefully by improving the algorithm here we don't need to. :)

> Improve master failover performance by reducing unnecessary agent retries.
> --------------------------------------------------------------------------
>
>                 Key: MESOS-7688
>                 URL: https://issues.apache.org/jira/browse/MESOS-7688
>             Project: Mesos
>          Issue Type: Improvement
>          Components: agent, master
>            Reporter: Benjamin Mahler
>              Labels: scalability
>         Attachments: 1.2.0.png, reregistration.perf.gz, reregistration.svg
>
>
> Currently, during a failover the agents will (re-)register with the master. 
> While the master is recovering, the master may drop messages from the agents, 
> and so the agents must retry registration using a backoff mechanism. For 
> large clusters, there can be a lot of overhead in processing unnecessary 
> retries from the agents, given that these messages must be deserialized and 
> contain all of the task / executor information many times over.
> In order to reduce this overhead, the idea is to avoid the need for agents to 
> blindly retry (re-)registration with the master. Two approaches for this are:
> (1) Update the MasterInfo in ZK when the master is recovered. This is a bit 
> of an abuse of MasterInfo unfortunately, but the idea is for agents to only 
> (re-)register when they see that the master reaches a recovered state. Once 
> recovered, the master will not drop messages, and therefore agents only need 
> to retry when the connection breaks.
> (2) Have the master reply with a retry message when it's in the recovering 
> state, so that agents get a clear signal that their messages were dropped. 
> The agents only retry when the connection breaks or they get a retry message. 
> This one is less optimal, because the master may have to process a lot of 
> messages and send retries, but once the master is recovered, the master will 
> process only a single (re-)registration from each agent. The number of 
> (re-)registrations that occur while the master is recovering can be reduced 
> to 1 in this approach if the master sends the retry message only after the 
> master completes recovery.



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