You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@flink.apache.org by "Matthias Pohl (Jira)" <ji...@apache.org> on 2022/12/21 10:27:00 UTC
[jira] [Commented] (FLINK-30474) DefaultMultipleComponentLeaderElectionService triggers HA backend change even if it's not the leader
[ https://issues.apache.org/jira/browse/FLINK-30474?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17650811#comment-17650811 ]
Matthias Pohl commented on FLINK-30474:
---------------------------------------
The leader check is actually handled in the {{MultipleComponentLeaderElectionDriver}} implementations (see [ZooKeeperMultipleComponentLeaderElectionDriver:203|https://github.com/apache/flink/blob/8ddfd590ebba7fc727e79db41b82d3d40a02b56a/flink-runtime/src/main/java/org/apache/flink/runtime/leaderelection/ZooKeeperMultipleComponentLeaderElectionDriver.java#L203] and [ZooKeeperMultipleComponentLeaderElectionDriver:223|https://github.com/apache/flink/blob/8ddfd590ebba7fc727e79db41b82d3d40a02b56a/flink-runtime/src/main/java/org/apache/flink/runtime/leaderelection/ZooKeeperMultipleComponentLeaderElectionDriver.java#L223] for ZooKeeper and [KubernetesMultipleComponentLeaderElectionDriver:238|https://github.com/apache/flink/blob/0290715a57b8d243586ab747b0cd2416c8081012/flink-kubernetes/src/main/java/org/apache/flink/kubernetes/highavailability/KubernetesMultipleComponentLeaderElectionDriver.java#L238] for Kubernetes. But this only triggers the sending of the change information which is then executed in a separate thread in [DefaultMultipleComponentLeaderElectionService#sendLeaderInformationChange|https://github.com/apache/flink/blob/715c3fdef515c4b7ac70c4abd52910c08d6ca662/flink-runtime/src/main/java/org/apache/flink/runtime/leaderelection/DefaultMultipleComponentLeaderElectionService.java#L247]. Therefore, the leader role could have changed in the meantime.
> DefaultMultipleComponentLeaderElectionService triggers HA backend change even if it's not the leader
> ----------------------------------------------------------------------------------------------------
>
> Key: FLINK-30474
> URL: https://issues.apache.org/jira/browse/FLINK-30474
> Project: Flink
> Issue Type: Bug
> Components: Runtime / Coordination
> Affects Versions: 1.16.0, 1.17.0, 1.15.3
> Reporter: Matthias Pohl
> Assignee: Matthias Pohl
> Priority: Critical
>
> {{DefaultMultipleComponentLeaderElectionService}} calls {{LeaderElectionEventHandler#onLeaderInformationChange}} in any case even though the contracts of that method states that it should be only called by the leader to update the HA backend information (see [JavaDoc|https://github.com/apache/flink/blob/5a2f220e31c50306a60aae8281f0ab4073fb85e1/flink-runtime/src/main/java/org/apache/flink/runtime/leaderelection/LeaderElectionEventHandler.java#L46-L50]).
--
This message was sent by Atlassian Jira
(v8.20.10#820010)