[jira] [Commented] (FLINK-27848) ZooKeeperLeaderElectionDriver keeps writing leader information, using up zxid

["Guo Weijie (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-27848?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17544668#comment-17544668 ] 

Guo Weijie commented on FLINK-27848:
------------------------------------

Hi [~xtsong] , I have prepared a pull request for this ticket, can you help to review it?

> ZooKeeperLeaderElectionDriver keeps writing leader information, using up zxid
> -----------------------------------------------------------------------------
>
>                 Key: FLINK-27848
>                 URL: https://issues.apache.org/jira/browse/FLINK-27848
>             Project: Flink
>          Issue Type: Bug
>          Components: Runtime / Coordination
>    Affects Versions: 1.15.0, 1.14.4
>            Reporter: Xintong Song
>            Assignee: Weijie Guo
>            Priority: Major
>              Labels: pull-request-available
>             Fix For: 1.14.5, 1.15.1
>
>
> After a leadership change, the new leader may keeps writing its information (which is identical) to ZK, causing the zxid on ZK quickly used up.
> The problem is that, in {{ZooKeeperLeaderElectionDriver#retrieveLeaderInformationFromZooKeeper}}, {{leaderElectionEventHandler.onLeaderInformationChange(LeaderInformation.empty())}} is called no matter {{childData}} is {{null}} or not. In case of non-null, this will cause the driver keeps re-writing the leader information to ZK.
> The problem was introduced in FLINK-24038, and only affects the legacy {{ZooKeeperHaServices}}. Thus, only 1.14 / 1.15 are affected.



--
This message was sent by Atlassian Jira
(v8.20.7#820007)