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https://issues.apache.org/jira/browse/OAK-4069?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15744921#comment-15744921
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Tomek Rękawek commented on OAK-4069:
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[~mreutegg], any further suggestions? Otherwise I plan to commit it on tomorrow 
(Wednesday) at 12:00.

> Use read concern majority when connected to a replica set
> ---------------------------------------------------------
>
>                 Key: OAK-4069
>                 URL: https://issues.apache.org/jira/browse/OAK-4069
>             Project: Jackrabbit Oak
>          Issue Type: Improvement
>          Components: mongomk
>            Reporter: Tomek Rękawek
>            Assignee: Tomek Rękawek
>              Labels: resilience
>             Fix For: 1.6, 1.5.16
>
>         Attachments: OAK-4069-2.patch, OAK-4069-3.patch, OAK-4069.patch
>
>
> Mongo 3.2 introduces new query option: {{readConcern}}. It allows to read 
> only these changes that have been already committed to the majority of 
> secondary instances.
> It prevents stale reads - a situation in which a change has been committed on 
> the primary (and read from it), but due to the network partition a new 
> primary is elected and the change is rolled back.
> We should use this new option (together with {{w:majority}} implemented in 
> OAK-3554) when running Oak on MongoDB replica set.
> References:
> * [Jepsen: MongoDB stale 
> reads|https://aphyr.com/posts/322-jepsen-mongodb-stale-reads]
> * [MongoDB documentation: Read Concern 
> in|https://docs.mongodb.org/manual/reference/read-concern/]



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