You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@cassandra.apache.org by "Brandon Williams (Jira)" <ji...@apache.org> on 2021/07/12 16:02:00 UTC

[jira] [Updated] (CASSANDRA-14930) decommission may cause timeout because messaging backlog is cleared

     [ https://issues.apache.org/jira/browse/CASSANDRA-14930?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Brandon Williams updated CASSANDRA-14930:
-----------------------------------------
    Status: Needs Reviewer  (was: Review In Progress)

> decommission may cause timeout because messaging backlog is cleared 
> --------------------------------------------------------------------
>
>                 Key: CASSANDRA-14930
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-14930
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Legacy/Coordination, Legacy/Core
>            Reporter: Zhao Yang
>            Assignee: Zhao Yang
>            Priority: Normal
>             Fix For: 3.0.x, 3.11.x
>
>
> On a 3-node cluster with RF=2, decommissioning a node may cause quorum write timeout because messaging backlog to decommissioned node is cleared via {{Gossiper#removeEndpoint() -> OutboundTcpConnection#closeSocket()}}.
>  (Timeout is less likely to happen with RF=3, because we can afford one less response)
> {code:java}
> What happened:
> 1. [WriteStage] before the leaving node is removed from tokenmetadata, the write endpoints are generated ( leaving endpoint is included )
> 2. [GossipStage] the leaving node is removed from tokenmetadata, no more future write handler will include leaving endpoints
> 3. [WriteStage] write handlers sends messages to messaging-service backlog
> 4. [GossipStage] messaging-service backlog is cleared, messages are not sent and connection closed
> 5. [WriteStage] write time out
>  {code}
> |patch|
> |[3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.0]|
> |[3.11|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.11]|
> We can avoid it by delaying to destroy messaging connection so that messages are sent and responded. This patch also avoids reopening already closed connection on {{MessagingService#convict()}}.
>  New messaging framework rewrite in {{Trunk}} avoids the issues by not clearing messaging backlog.



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

---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org