[jira] [Commented] (CURATOR-447) TreeCache: Improve memory usage and concurrent update logic

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CURATOR-447?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16353361#comment-16353361 ] 

ASF GitHub Bot commented on CURATOR-447:
----------------------------------------

Github user njhill commented on the issue:

    https://github.com/apache/curator/pull/250
  
    @dragonsinth any interest in these changes? Maybe I should rename the PR since as you pointed out the memory saving aspect isn't very significant (I measured about 2% on a cache of 50k empty nodes), but hopefully the state and update logic simplification is beneficial?


> TreeCache: Improve memory usage and concurrent update logic
> -----------------------------------------------------------
>
>                 Key: CURATOR-447
>                 URL: https://issues.apache.org/jira/browse/CURATOR-447
>             Project: Apache Curator
>          Issue Type: Improvement
>          Components: Recipes
>    Affects Versions: 3.3.0, 2.12.0
>            Reporter: Nick Hill
>            Priority: Minor
>              Labels: performance
>
> Jira https://issues.apache.org/jira/browse/CURATOR-374 reduced per-node memory usage in {{TreeCache}}. It can be improved further via removal of the {{nodeState}} field - its {{LIVE}} state corresponds exactly to the adjacent {{childData}} field being non-null, and a sentinel {{ChildData}} value can be used for the {{DEAD}} state. This simplification also reduces the room for bugs and state inconsistencies.
> Other improvements included:
> * A further simplification to have {{TreeNode}} extend {{AtomicReference}}, which obviates the need for an explicit {{childData}} field
> * More robust cache update logic (in get-children and get-data event callbacks)
> * Avoid overhead of incrementing/decrementing the {{outstandingOps}} atomic integer post-initialization



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)