[jira] Commented: (CASSANDRA-1530) More-efficient cross-DC replication

["Gary Dusbabek (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-1530?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12991477#comment-12991477 ] 

Gary Dusbabek commented on CASSANDRA-1530:
------------------------------------------

* Message.getMessageId() is still being used in SP@156, but I'm pretty sure this line can be taken away because the callback is added when MS.sendRR is eventually called.
* I saw you got rid of MoveMessageVerbHandler, but not LoadBalancer.
* +1 to regenerating the test blobs.

> More-efficient cross-DC replication
> -----------------------------------
>
>                 Key: CASSANDRA-1530
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1530
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Jonathan Ellis
>            Assignee: Jonathan Ellis
>             Fix For: 0.7.1
>
>         Attachments: 1530-2.txt
>
>   Original Estimate: 24h
>  Remaining Estimate: 24h
>
> Currently the coordinator node sends writes to each replica.  In multi-dc situations, it would be more efficient to have the coordinator talk to a single node in each DC, which would forward the writes to the other replicas local to it.  (All replicas would continue to ack to the coordinator.)
> Shouldn't be difficult to add a header to RMVH saying "consult the Strategy to see who else is local to you and queue it off to them as well."
> For example, consider two data centers with the following nodes:
> DC1: A, B, C
> DC2: D, E, F
> A client connected to node A performs an insert that should be replicated to {B,C,E,F}.  Currently, A will send a MUTATION verb to each of those nodes directly.  But communication to E and F is relatively expensive since they are in the other data center from A.  So we'd like to send the mutation to just one, say E, with a tag saying "forward this to F as well."

-- 
This message is automatically generated by JIRA.
-
For more information on JIRA, see: http://www.atlassian.com/software/jira