You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@zookeeper.apache.org by "Patrick Hunt (JIRA)" <ji...@apache.org> on 2008/10/14 23:05:44 UTC

[jira] Assigned: (ZOOKEEPER-140) Deadlock in QuorumCnxManager

     [ https://issues.apache.org/jira/browse/ZOOKEEPER-140?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Patrick Hunt reassigned ZOOKEEPER-140:
--------------------------------------

    Assignee: Flavio Paiva Junqueira

> Deadlock in QuorumCnxManager
> ----------------------------
>
>                 Key: ZOOKEEPER-140
>                 URL: https://issues.apache.org/jira/browse/ZOOKEEPER-140
>             Project: Zookeeper
>          Issue Type: Bug
>    Affects Versions: 3.0.0
>            Reporter: Flavio Paiva Junqueira
>            Assignee: Flavio Paiva Junqueira
>             Fix For: 3.0.0
>
>
> Frequently the servers deadlock in QuorumCnxManager:initiateConnection on
> s.read(msgBuffer) when reading the challenge from the peer.
> Calls to initiateConnection and receiveConnection are synchronized, so only one or the other can be executing at a time. This prevents two connections from opening between the same pair of servers.
> However, it seems that this leads to deadlock, as in this scenario:
> {noformat}
> A (initiate --> B)
> B (initiate --> C)
> C (initiate --> A)
> {noformat}
> initiateConnection can only complete when receiveConnection runs on the remote peer and answers the challenge. If all servers are blocked in initiateConnection, receiveConnection never runs and leader election halts.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.