You are viewing a plain text version of this content. The canonical link for it is here.
Posted to hdfs-dev@hadoop.apache.org by "Todd Lipcon (Resolved) (JIRA)" <ji...@apache.org> on 2011/12/21 04:05:33 UTC

[jira] [Resolved] (HDFS-2693) Synchronization issues around state transition

     [ https://issues.apache.org/jira/browse/HDFS-2693?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Todd Lipcon resolved HDFS-2693.
-------------------------------

       Resolution: Fixed
    Fix Version/s: HA branch (HDFS-1623)
     Hadoop Flags: Reviewed

Committed to branch, thx for the reviews Eli.
                
> Synchronization issues around state transition
> ----------------------------------------------
>
>                 Key: HDFS-2693
>                 URL: https://issues.apache.org/jira/browse/HDFS-2693
>             Project: Hadoop HDFS
>          Issue Type: Sub-task
>          Components: ha, name-node
>    Affects Versions: HA branch (HDFS-1623)
>            Reporter: Todd Lipcon
>            Assignee: Todd Lipcon
>            Priority: Critical
>             Fix For: HA branch (HDFS-1623)
>
>         Attachments: hdfs-2693.txt, hdfs-2693.txt, hdfs-2693.txt, hdfs-2693.txt, hdfs-2693.txt
>
>
> Currently when the NN changes state, it does so without synchronization. In particular, the state transition function does:
> (1) leave old state
> (2) change state variable
> (3) enter new state
> This means that the NN is marked as "active" before it has actually transitioned to active mode and opened its edit logs. This gives a window where write transactions can come in and the {{checkOperation}} allows them, but then they fail because the edit log is not yet opened.

--
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