zookeeper-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Germán Blanco (JIRA) <j...@apache.org>
Subject [jira] [Commented] (ZOOKEEPER-1808) Add version to FLE notifications for 3.4 branch
Date Sat, 09 Nov 2013 06:10:18 GMT

    [ https://issues.apache.org/jira/browse/ZOOKEEPER-1808?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13818034#comment-13818034

Germán Blanco commented on ZOOKEEPER-1808:

If I am not wrong, not-updated servers will interpret the new length as a very large number,
try to read all those bytes and wait for a very long time.
I don't see any way to encode the version in the existing fields of the message, it will always
confuse not-updated servers. One backwards compatible option that I see at the moment is adding
version at the end and using a correct greater length so that non-updated servers handle updated
servers using the current backwards compatibility code (ignoring peerEpoch and extracting
it from zxid). 
Another might be encoding the version in the sid that gets send in the connection establishment.
Maybe updated servers could start using the higher bits of the long in the same way that you
have done for the length of the message. They will be seen as very high sids by not-updated
servers, but maybe that is not a problem.

> Add version to FLE notifications for 3.4 branch
> -----------------------------------------------
>                 Key: ZOOKEEPER-1808
>                 URL: https://issues.apache.org/jira/browse/ZOOKEEPER-1808
>             Project: ZooKeeper
>          Issue Type: Sub-task
>            Reporter: Flavio Junqueira
>            Assignee: Flavio Junqueira
>             Fix For: 3.4.6
>         Attachments: ZOOKEEPER-1808.patch, ZOOKEEPER-1808.patch, ZOOKEEPER-1808.patch
> Add version to notification messages so that we can differentiate messages during rolling
upgrades. This task is for the 3.4 branch only. 

This message was sent by Atlassian JIRA

View raw message