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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:
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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 improve this by, 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, 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.
> 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 improve this by, 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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