jackrabbit-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Lars Trieloff (JIRA)" <j...@apache.org>
Subject [jira] Commented: (JCR-642) Support flat content hierarchies
Date Mon, 03 Aug 2009 15:49:14 GMT

    [ https://issues.apache.org/jira/browse/JCR-642?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12738396#action_12738396
] 

Lars Trieloff commented on JCR-642:
-----------------------------------

> There would be no change to the persistence manager! 
> ...unfortunately, quite a lot of effort elsewhere in the core. 

I think that's the best news I have heard on this issue in a long time. We do not have to

- break APIs
- break existing third-party code
- break existing persisted repositories

Once we fix it, it is only an incremental change for existing users with long lists - their
B-Tree that they did not know about will be re-balanced with the next write and
that's it.

> Support flat content hierarchies
> --------------------------------
>
>                 Key: JCR-642
>                 URL: https://issues.apache.org/jira/browse/JCR-642
>             Project: Jackrabbit Content Repository
>          Issue Type: Improvement
>          Components: jackrabbit-core
>            Reporter: Jukka Zitting
>
> The current best practice with Jackrabbit is to avoid flat content structures due to
performance concerns.
> These concerns are caused by the fact that the NodeState implementation requires the
list of child node names and identifiers to be available at all times.  In fact many (all?)
current persistence managers implement this requirement by storing and loading this list as
a part of the serialized node state. When this list grows, the performance and memory overhead
of managing the list grows as well. As a side note, this also creates potential consistency
issues since the parent/child links are stored both within the child list of the parent node
and as the parent link of the child node.
> To solve this issue, I believe we need to break the tight bonding between the node state
and the list of child nodes. This will likely require major refactoring of the Jackrabbit
core, including breaking the NodeState and PersistenceManager interfaces, so I don't expect
a solution in near future. However, we should start thinking about how to best do this, and
at least be concerned about building in any more assumptions about the list of child nodes
always being readily available.

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


Mime
View raw message