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https://issues.apache.org/jira/browse/COUCHDB-2964?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15180747#comment-15180747
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Nick Vatamaniuc commented on COUCHDB-2964:
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Replicator manager currently uses "longpoll" mode just like the 
couch_replicator code.  Since replicator manager in 2.0 uses change feeds from 
local shards, it is interesting to investigate switching to "normal" mode.

Details:

Previous couch_replicator's change feeds go through the fabric layer so 
longpoll is needed because the set of shards which signaled the update, might 
not be the shards changes feed will hit. If normal is used then the change feed 
could immediately return without waiting for the new change. Longpoll mode 
ensures there is a wait for shards to receive the change and only then return.

CouchDB 2.0 replicator manager uses change feeds on individual shards. It seems 
even though "longpoll" mode will still work (replicator manager is notified 
there is an update to the database, then get changes from last checkpoint to 
the latest, and then saves the new checkpoint),  normal" mode might be more 
semantically correct, as effectively "longpoll" is used as normal in most cases.

> Investigate switching replicator manager change feeds to using "normal" 
> instead of "longpoll"
> ---------------------------------------------------------------------------------------------
>
>                 Key: COUCHDB-2964
>                 URL: https://issues.apache.org/jira/browse/COUCHDB-2964
>             Project: CouchDB
>          Issue Type: Improvement
>          Components: Replication
>            Reporter: Nick Vatamaniuc
>




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