[ 
https://issues.apache.org/jira/browse/HIVE-10191?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14528129#comment-14528129
 ] 

Prasanth Jayachandran commented on HIVE-10191:
----------------------------------------------

Looks good to me. +1. Will be good to add a note in javadoc saying applications 
using ORC writers should synchronize write operation.

> ORC: Cleanup writer per-row synchronization
> -------------------------------------------
>
>                 Key: HIVE-10191
>                 URL: https://issues.apache.org/jira/browse/HIVE-10191
>             Project: Hive
>          Issue Type: Bug
>          Components: File Formats
>    Affects Versions: 1.2.0
>            Reporter: Gopal V
>            Assignee: Gopal V
>         Attachments: HIVE-10191.1.patch, HIVE-10191.2.patch, 
> HIVE-10191.3.patch, HIVE-10191.4.patch
>
>
> ORC writers were originally meant to be thread-safe, but in the present day 
> implementation each ORC writer is entirely share-nothing which converts most 
> of the synchronized blocks in ORC as entirely uncontested locks.
> These uncontested locks prevent the JVM from inlining/optimizing these 
> methods, while adding no extra thread-safety to the ORC writers.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to