Apache Flink - Throttling stream flow

[M Singh]

Hi:

I have an Flink streaming application that invokes  some other web services.  However the webservices have limited throughput.  So I wanted to find out if there any recommendations on how to throttle the Flink datastream so that they don't overload the downstrream services.  I am using Kinesis as source and sink in my application.

Please let me know if there any hooks available in Flink, what are the patterns that can be used and what are the best practices/pitfalls for using them.

Thanks 

Mans

[Caizhi Weng]

Hi,

As far as I know, Flink currently doesn't have a built-in throttling function. You can write your own user-defined function to achieve this. Your function just gives out what it reads in and limits the speed it gives out records at the same time.

If you're not familiar with user-defined functions, see https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/udfs.html

Here is a throttling iterator example: https://github.com/apache/flink/blob/master/flink-examples/flink-examples-streaming/src/main/java/org/apache/flink/streaming/examples/utils/ThrottledIterator.java

M Singh <[hidden email]> 于2019年11月25日周一 上午5:50写道：

Hi:

I have an Flink streaming application that invokes  some other web services.  However the webservices have limited throughput.  So I wanted to find out if there any recommendations on how to throttle the Flink datastream so that they don't overload the downstrream services.  I am using Kinesis as source and sink in my application.

Please let me know if there any hooks available in Flink, what are the patterns that can be used and what are the best practices/pitfalls for using them.

Thanks 

Mans

[Thomas Julian]

related

https://issues.apache.org/jira/browse/FLINK-13792

Regards,

Julian.

---- On Mon, 25 Nov 2019 15:25:14 +0530 Caizhi Weng <[hidden email]> wrote ----

Hi,

As far as I know, Flink currently doesn't have a built-in throttling function. You can write your own user-defined function to achieve this. Your function just gives out what it reads in and limits the speed it gives out records at the same time.

If you're not familiar with user-defined functions, see https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/udfs.html

Here is a throttling iterator example: https://github.com/apache/flink/blob/master/flink-examples/flink-examples-streaming/src/main/java/org/apache/flink/streaming/examples/utils/ThrottledIterator.java

M Singh <[hidden email]> 于2019年11月25日周一 上午5:50写道：

Hi:

I have an Flink streaming application that invokes  some other web services.  However the webservices have limited throughput.  So I wanted to find out if there any recommendations on how to throttle the Flink datastream so that they don't overload the downstrream services.  I am using Kinesis as source and sink in my application.

Please let me know if there any hooks available in Flink, what are the patterns that can be used and what are the best practices/pitfalls for using them.

Thanks 

Mans

[M Singh]

Thanks Ciazhi & Thomas for your responses.

I read the throttling example but want to see if that work with a distributed broker like Kinesis and how to have throttling feedback to the Kinesis source so that it can vary the rate without interfering with watermarks, etc.

Thanks again 

Mans

On Monday, November 25, 2019, 05:55:21 AM EST, Thomas Julian <[hidden email]> wrote:

related

https://issues.apache.org/jira/browse/FLINK-13792

Regards,

Julian.

---- On Mon, 25 Nov 2019 15:25:14 +0530 Caizhi Weng <[hidden email]> wrote ----

Hi,

As far as I know, Flink currently doesn't have a built-in throttling function. You can write your own user-defined function to achieve this. Your function just gives out what it reads in and limits the speed it gives out records at the same time.

If you're not familiar with user-defined functions, see https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/udfs.html

Here is a throttling iterator example: https://github.com/apache/flink/blob/master/flink-examples/flink-examples-streaming/src/main/java/org/apache/flink/streaming/examples/utils/ThrottledIterator.java

M Singh <[hidden email]> 于2019年11月25日周一 上午5:50写道：

Hi:

I have an Flink streaming application that invokes  some other web services.  However the webservices have limited throughput.  So I wanted to find out if there any recommendations on how to throttle the Flink datastream so that they don't overload the downstrream services.  I am using Kinesis as source and sink in my application.

Please let me know if there any hooks available in Flink, what are the patterns that can be used and what are the best practices/pitfalls for using them.

Thanks 

Mans

[Rong Rong]

Hi Mans,

is this what you are looking for [1][2]?

--

Rong

[1] https://issues.apache.org/jira/browse/FLINK-11501

[2] https://github.com/apache/flink/pull/7679

On Mon, Nov 25, 2019 at 3:29 AM M Singh <[hidden email]> wrote:

Thanks Ciazhi & Thomas for your responses.

I read the throttling example but want to see if that work with a distributed broker like Kinesis and how to have throttling feedback to the Kinesis source so that it can vary the rate without interfering with watermarks, etc.

Thanks again 

Mans

On Monday, November 25, 2019, 05:55:21 AM EST, Thomas Julian <[hidden email]> wrote:

related

https://issues.apache.org/jira/browse/FLINK-13792

Regards,

Julian.

---- On Mon, 25 Nov 2019 15:25:14 +0530 Caizhi Weng <[hidden email]> wrote ----

Hi,

As far as I know, Flink currently doesn't have a built-in throttling function. You can write your own user-defined function to achieve this. Your function just gives out what it reads in and limits the speed it gives out records at the same time.

If you're not familiar with user-defined functions, see https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/udfs.html

Here is a throttling iterator example: https://github.com/apache/flink/blob/master/flink-examples/flink-examples-streaming/src/main/java/org/apache/flink/streaming/examples/utils/ThrottledIterator.java

M Singh <[hidden email]> 于2019年11月25日周一 上午5:50写道：

Hi:

I have an Flink streaming application that invokes  some other web services.  However the webservices have limited throughput.  So I wanted to find out if there any recommendations on how to throttle the Flink datastream so that they don't overload the downstrream services.  I am using Kinesis as source and sink in my application.

Please let me know if there any hooks available in Flink, what are the patterns that can be used and what are the best practices/pitfalls for using them.

Thanks 

Mans

[M Singh]

Thanks Rong for your references. 

From what I can see, the rate limiter is initialized statically.  But if the load on downstream services varies, is there a way to update the rater limiter at runtime ?  Please let me know if I missed anything.

Thanks again for your advice.

On Wednesday, November 27, 2019, 11:32:06 AM EST, Rong Rong <[hidden email]> wrote:

Hi Mans,

is this what you are looking for [1][2]?

--

Rong

[1] https://issues.apache.org/jira/browse/FLINK-11501

[2] https://github.com/apache/flink/pull/7679

On Mon, Nov 25, 2019 at 3:29 AM M Singh <[hidden email]> wrote:

Thanks Ciazhi & Thomas for your responses.

I read the throttling example but want to see if that work with a distributed broker like Kinesis and how to have throttling feedback to the Kinesis source so that it can vary the rate without interfering with watermarks, etc.

Thanks again 

Mans

On Monday, November 25, 2019, 05:55:21 AM EST, Thomas Julian <[hidden email]> wrote:

related

https://issues.apache.org/jira/browse/FLINK-13792

Regards,

Julian.

---- On Mon, 25 Nov 2019 15:25:14 +0530 Caizhi Weng <[hidden email]> wrote ----

Hi,

As far as I know, Flink currently doesn't have a built-in throttling function. You can write your own user-defined function to achieve this. Your function just gives out what it reads in and limits the speed it gives out records at the same time.

If you're not familiar with user-defined functions, see https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/udfs.html

Here is a throttling iterator example: https://github.com/apache/flink/blob/master/flink-examples/flink-examples-streaming/src/main/java/org/apache/flink/streaming/examples/utils/ThrottledIterator.java

M Singh <[hidden email]> 于2019年11月25日周一 上午5:50写道：

Hi:

I have an Flink streaming application that invokes  some other web services.  However the webservices have limited throughput.  So I wanted to find out if there any recommendations on how to throttle the Flink datastream so that they don't overload the downstrream services.  I am using Kinesis as source and sink in my application.

Please let me know if there any hooks available in Flink, what are the patterns that can be used and what are the best practices/pitfalls for using them.

Thanks 

Mans