[ 
https://issues.apache.org/jira/browse/FLINK-8516?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16350048#comment-16350048
 ] 

ASF GitHub Bot commented on FLINK-8516:
---------------------------------------

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

    https://github.com/apache/flink/pull/5393#discussion_r165589453
  
    --- Diff: 
flink-connectors/flink-connector-kinesis/src/main/java/org/apache/flink/streaming/connectors/kinesis/util/KinesisShardAssigner.java
 ---
    @@ -0,0 +1,57 @@
    +/*
    + * Licensed to the Apache Software Foundation (ASF) under one or more
    + * contributor license agreements.  See the NOTICE file distributed with
    + * this work for additional information regarding copyright ownership.
    + * The ASF licenses this file to You under the Apache License, Version 2.0
    + * (the "License"); you may not use this file except in compliance with
    + * the License.  You may obtain a copy of the License at
    + *
    + *    http://www.apache.org/licenses/LICENSE-2.0
    + *
    + * Unless required by applicable law or agreed to in writing, software
    + * distributed under the License is distributed on an "AS IS" BASIS,
    + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    + * See the License for the specific language governing permissions and
    + * limitations under the License.
    + */
    +
    +package org.apache.flink.streaming.connectors.kinesis.util;
    +
    +import 
org.apache.flink.streaming.connectors.kinesis.model.StreamShardHandle;
    +
    +import java.io.Serializable;
    +
    +/**
    + * Utility to map Kinesis shards to Flink subtask indices.
    + */
    +public interface KinesisShardAssigner extends Serializable {
    +    /**
    +    * Returns the index of the target subtask that a specific Kafka 
partition should be
    +    * assigned to. For return values outside the subtask range, modulus 
operation will
    +    * be applied automatically, hence it is also valid to just return a 
hash code.
    +    *
    +    * <p>The resulting distribution of shards has the following contract:
    --- End diff --
    
    The resulting distribution of shards "**should**" have the following 
contract.
    
    i.e., we can't guarantee it, instead the user implementation should 
guarantee it.


> FlinkKinesisConsumer does not balance shards over subtasks
> ----------------------------------------------------------
>
>                 Key: FLINK-8516
>                 URL: https://issues.apache.org/jira/browse/FLINK-8516
>             Project: Flink
>          Issue Type: Bug
>          Components: Kinesis Connector
>    Affects Versions: 1.4.0, 1.3.2, 1.5.0
>            Reporter: Thomas Weise
>            Assignee: Thomas Weise
>            Priority: Major
>
> The hash code of the shard is used to distribute discovered shards over 
> subtasks round robin. This works as long as shard identifiers are sequential. 
> After shards are rebalanced in Kinesis, that may no longer be the case and 
> the distribution become skewed.



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

Reply via email to