[jira] [Issue Comment Edited] (CASSANDRA-1391) Allow Concurrent Schema Migrations

["T Jake Luciani (Issue Comment Edited) (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-1391?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13149743#comment-13149743 ] 

T Jake Luciani edited comment on CASSANDRA-1391 at 11/14/11 5:05 PM:
---------------------------------------------------------------------

By moving to CF based migration logic it would be very useful to have the logic abstracted from schemas so it can be used for other use cases.

Migrations give you the following:

  * RF = N where N is the size of the ring.
  * All changes are "pushed" to new nodes when they join the ring.
  * previously sent data is available locally on startup


                
      was (Author: tjake):
    My moving to CF based migration logic it would be very useful to have the logic abstracted so it can be used for other use cases.

Migrations give you the following:

  * RF = N where N is the size of the ring.
  * All changes are "pushed" to new nodes when they join the ring.
  * previously sent data is available locally on startup


                  
> Allow Concurrent Schema Migrations
> ----------------------------------
>
>                 Key: CASSANDRA-1391
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1391
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>    Affects Versions: 0.7.0
>            Reporter: Stu Hood
>            Assignee: Pavel Yaskevich
>             Fix For: 1.1
>
>         Attachments: CASSANDRA-1391.patch
>
>
> CASSANDRA-1292 fixed multiple migrations started from the same node to properly queue themselves, but it is still possible for migrations initiated on different nodes to conflict and leave the cluster in a bad state. Since the system_add/drop/rename methods are accessible directly from the client API, they should be completely safe for concurrent use.
> It should be possible to allow for most types of concurrent migrations by converting the UUID schema ID into a VersionVectorClock (as provided by CASSANDRA-580).

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira