[ 
https://issues.apache.org/jira/browse/FLINK-2897?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14970756#comment-14970756
 ] 

ASF GitHub Bot commented on FLINK-2897:
---------------------------------------

Github user fhueske commented on a diff in the pull request:

    https://github.com/apache/flink/pull/1292#discussion_r42849790
  
    --- Diff: 
flink-runtime/src/main/java/org/apache/flink/runtime/operators/shipping/OutputEmitter.java
 ---
    @@ -143,14 +148,25 @@ public OutputEmitter(ShipStrategyType strategy, 
TypeComparator<T> comparator, Pa
        
        // 
--------------------------------------------------------------------------------------------
     
    +   private int[] forward() {
    +           if (this.channels == null) {
    --- End diff --
    
    This method preserves the behavior of `FORWARD` only if `numberOfChannels` 
is always 0 when `FORWARD` is configured which is out of control of the 
`OutputEmitter`.
    Should we add a check somewhere (e.g., in this condition to reduce the 
overhead) to ensure that `numberOfChannels` is acutally 0 for `FORWARD`?


> Use distinct initial indices for OutputEmitter round-robin
> ----------------------------------------------------------
>
>                 Key: FLINK-2897
>                 URL: https://issues.apache.org/jira/browse/FLINK-2897
>             Project: Flink
>          Issue Type: Improvement
>          Components: Distributed Runtime
>    Affects Versions: 0.10
>            Reporter: Greg Hogan
>            Assignee: Greg Hogan
>
> Currently, when performing a round-robin partitioning each task will 
> sequentially partition starting with partition "1". This is fine in the usual 
> case where the number of partitioned objects greatly exceeds the number of 
> channels. However, in the case where the number of objects is relatively few 
> (each, perhaps, requiring a large computation or access to an external 
> system) it would be much better to begin partitioning at distinct indices 
> (the task index).



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

Reply via email to