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https://issues.apache.org/jira/browse/FLINK-4574?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Tzu-Li (Gordon) Tai updated FLINK-4574:
---------------------------------------
    Description: 
As pointed out by [~rmetzger], right now the fetch interval implementation in 
the {{ShardConsumer}} class of the Kinesis consumer can lead to much longer 
interval times than specified by the user, ex. say the specified fetch interval 
is {{f}}, it takes {{x}} to complete a {{getRecords()}} call, and {{y}} to 
complete processing the fetched records for emitting, than the actual interval 
between each fetch is actually {{f+x+y}}.

The main problem with this is that we can never guarantee how much time has 
past since the last {{getRecords}} call, thus can not guarantee that returned 
shard iterators will not have expired the next time we use them, even if we 
limit the user-given value for {{f}} to not be longer than the iterator expire 
time.

I propose to change to, per {{ShardConsumer}}, use a 
{{ScheduledExecutorService}} to do the fixed-interval fetching, and a separate 
blocking queue that collects the fetched records for emitting.

  was:
As pointed out by [~rmetzger], right now the fetch interval implementation in 
the {{ShardConsumer}} class of the Kinesis consumer can lead to much longer 
interval times than specified by the user, ex. say the specified fetch interval 
is {{f}}, it takes {{x}} to complete a {{getRecords()}} call, and {{y}} to 
complete processing the fetched records for emitting, than the actual interval 
between each fetch is actually {{f+x+y}}.

The main problem with this is that we can never guarantee how much time has 
past since the last {{getRecords}} call, thus can not guarantee that returned 
shard iterators will not have expired the next time we use them.

I propose to change to, per {{ShardConsumer}}, use a 
{{ScheduledExecutorService}} to do the fixed-interval fetching, and a separate 
blocking queue that collects the fetched records for emitting.


> Strengthen fetch interval implementation in Kinesis consumer
> ------------------------------------------------------------
>
>                 Key: FLINK-4574
>                 URL: https://issues.apache.org/jira/browse/FLINK-4574
>             Project: Flink
>          Issue Type: Improvement
>          Components: Kinesis Connector
>    Affects Versions: 1.1.0
>            Reporter: Tzu-Li (Gordon) Tai
>             Fix For: 1.2.0, 1.1.3
>
>
> As pointed out by [~rmetzger], right now the fetch interval implementation in 
> the {{ShardConsumer}} class of the Kinesis consumer can lead to much longer 
> interval times than specified by the user, ex. say the specified fetch 
> interval is {{f}}, it takes {{x}} to complete a {{getRecords()}} call, and 
> {{y}} to complete processing the fetched records for emitting, than the 
> actual interval between each fetch is actually {{f+x+y}}.
> The main problem with this is that we can never guarantee how much time has 
> past since the last {{getRecords}} call, thus can not guarantee that returned 
> shard iterators will not have expired the next time we use them, even if we 
> limit the user-given value for {{f}} to not be longer than the iterator 
> expire time.
> I propose to change to, per {{ShardConsumer}}, use a 
> {{ScheduledExecutorService}} to do the fixed-interval fetching, and a 
> separate blocking queue that collects the fetched records for emitting.



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