[jira] [Commented] (SOLR-14356) PeerSync with hanging nodes

["Cao Manh Dat (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/SOLR-14356?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17068520#comment-17068520 ] 

Cao Manh Dat commented on SOLR-14356:
-------------------------------------

Second thought, I think it is sufficient now to just add the Exception to the list and revisit the retry problem in another issue. The reason here is
 * We already count ConnectTimeoutException as success
 * The more I think about how a replica count on the result of SyncStrategy to become leader the more I feel it error-prone. Will open another issue for this.

> PeerSync with hanging nodes
> ---------------------------
>
>                 Key: SOLR-14356
>                 URL: https://issues.apache.org/jira/browse/SOLR-14356
>             Project: Solr
>          Issue Type: Improvement
>      Security Level: Public(Default Security Level. Issues are Public) 
>            Reporter: Cao Manh Dat
>            Priority: Major
>         Attachments: SOLR-14356.patch
>
>
> Right now in {{PeerSync}} (during leader election), in case of exception on requesting versions to a node, we will skip that node if exception is one the following type
> * ConnectTimeoutException
> * NoHttpResponseException
> * SocketException
> Sometime the other node basically hang but still accept connection. In that case SocketTimeoutException is thrown and we consider the {{PeerSync}} process as failed and the whole shard just basically leaderless forever (as long as the hang node still there).
> We can't just blindly adding {{SocketTimeoutException}} to above list, since [~shalin] mentioned that sometimes timeout can happen because of genuine reasons too e.g. temporary GC pause.
> I think the general idea here is we obey {{leaderVoteWait}} restriction and retry doing sync with others in case of connection/timeout exception happen.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@lucene.apache.org
For additional commands, e-mail: issues-help@lucene.apache.org