[ 
https://issues.apache.org/jira/browse/HDFS-16891?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17678397#comment-17678397
 ] 

ASF GitHub Bot commented on HDFS-16891:
---------------------------------------

cnauroth merged PR #5300:
URL: https://github.com/apache/hadoop/pull/5300




> Avoid the overhead of copy-on-write exception list while loading inodes sub 
> sections in parallel
> ------------------------------------------------------------------------------------------------
>
>                 Key: HDFS-16891
>                 URL: https://issues.apache.org/jira/browse/HDFS-16891
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: namenode
>    Affects Versions: 3.3.4
>            Reporter: Viraj Jasani
>            Assignee: Viraj Jasani
>            Priority: Major
>              Labels: pull-request-available
>
> If we enable parallel loading and persisting of inodes from/to fs image, we 
> get the benefit of improved performance. However, while loading sub-sections 
> INODE_DIR_SUB and INODE_SUB, if we encounter any errors, we use copy-on-write 
> list to maintain the list of exceptions. Since our usecase is not to iterate 
> over this list while executor threads are adding new elements to the list, 
> using copy-on-write is bit of an overhead for this usecase.
> It would be better to synchronize adding new elements to the list rather than 
> having the list copy all elements over every time new element is added to the 
> list.



--
This message was sent by Atlassian Jira
(v8.20.10#820010)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org

Reply via email to