[
https://issues.apache.org/jira/browse/HELIX-681?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16408163#comment-16408163
]
ASF GitHub Bot commented on HELIX-681:
--------------------------------------
Github user lei-xia commented on a diff in the pull request:
https://github.com/apache/helix/pull/152#discussion_r176143399
--- Diff:
helix-core/src/main/java/org/apache/helix/messaging/handling/HelixTask.java ---
@@ -168,7 +169,14 @@ public HelixTaskResult call() {
// forward relay messages attached to this message to other
participants
if (taskResult.isSuccess()) {
- forwardRelayMessages(accessor, _message,
taskResult.getCompleteTime());
+ try {
+ forwardRelayMessages(accessor, _message,
taskResult.getCompleteTime());
+ } catch (Exception e) {
+ // Fail to send relay message should not result in a task
execution failure
+ // Currently we don't log error to ZK to reduce writes as when
accessor throws
+ // exception, ZK might not be in good condition.
+ logger.error("Failed to send relay messages.", e);
--- End diff --
logger.warn should be fine, this is not fatal error.
> Participant should not fail state transition on fail to delete / relay message
> ------------------------------------------------------------------------------
>
> Key: HELIX-681
> URL: https://issues.apache.org/jira/browse/HELIX-681
> Project: Apache Helix
> Issue Type: Bug
> Reporter: Hao Zhang
> Priority: Major
>
> Currently we have a general try-catch block in HelixTask and
> HelixTaskExecutor, which, upon any exception thrown from state transition
> routine, will fail state transition. However there are at least the following
> cases in which state transition should be considered as successful:
> * When we fail to delete message after successfully handled message and
> updated current state -> this is because we already completed state
> transition and current state is consistent between participant and ZK
> * When we fail to send out relay message > as relay message provides only
> best effort of delivering messages, which has nothing to do with state
> transition's results. In case of fail to relay message, controller will
> resend message which ensures correctness.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
