Re: Flink custom parallel data source
Please note that SourceFunction API is deprecated and is due to be removed, possibly in the next major version of Flink. Ideally you should not be manually spawning threads in your Flink applications. Typically you would only perform data fetching in the sources and do processing in the subsequent operators which you can scale independently from the source parallelism. Can you describe what you are trying to achieve? Best, Alexander Fedulov On Tue, 31 Oct 2023 at 07:22, Kamal Mittal via user wrote: > Hello Community, > > > > I need to have a custom parallel data source (Flink ParallelSourceFunction) > for fetching data based on some custom logic. In this source function, > opening multiple threads via java thread pool to distribute work further. > > > > These threads share Flink provided ‘SourceContext’ and collect records via > source_context.collect() method. > > > > Is it ok to share source context in separate threads and get data? > > > > Is there any issue for downstream operators due to above design? > > > > Rgds, > > Kamal >
RE: Flink custom parallel data source
Hello, We are writing TCP server socket custom source function in which TCP server socket listener will accept connections and read data. Single Custom source server socket function – ServerSocket serversocket = new ServerSocket(); Now using thread pool accept multiple connections in separate threads = new Runnable () -> serversocket.accept(); So client socket will be accepted and given to separate thread for read data from TCP stream. Rgds, Kamal From: Alexander Fedulov Sent: 31 October 2023 04:03 PM To: Kamal Mittal Cc: user@flink.apache.org Subject: Re: Flink custom parallel data source Please note that SourceFunction API is deprecated and is due to be removed, possibly in the next major version of Flink. Ideally you should not be manually spawning threads in your Flink applications. Typically you would only perform data fetching in the sources and do processing in the subsequent operators which you can scale independently from the source parallelism. Can you describe what you are trying to achieve? Best, Alexander Fedulov On Tue, 31 Oct 2023 at 07:22, Kamal Mittal via user mailto:user@flink.apache.org>> wrote: Hello Community, I need to have a custom parallel data source (Flink ParallelSourceFunction) for fetching data based on some custom logic. In this source function, opening multiple threads via java thread pool to distribute work further. These threads share Flink provided ‘SourceContext’ and collect records via source_context.collect() method. Is it ok to share source context in separate threads and get data? Is there any issue for downstream operators due to above design? Rgds, Kamal
Re: Flink custom parallel data source
Flink natively supports a pull-based model for sources, where the source operators request data from the external system when they are ready to process it. Implementing a TCP server socket operator essentially creates a push-based source, which could lead to backpressure problems if the data ingestion rate exceeds the processing rate. You also lose any delivery guarantees because Flink's fault tolerance model relies on having replayable sources. Is using a message broker not feasible in your case? Best, Alexander Fedulov On Tue, 31 Oct 2023 at 13:08, Kamal Mittal wrote: > Hello, > > > > We are writing TCP server socket custom source function in which TCP > server socket listener will accept connections and read data. > > Single Custom source server socket function – ServerSocket *serversocket* = > new ServerSocket(); > > Now using thread pool accept multiple connections in separate threads = new > *Runnable* () -> *serversocket*.accept(); > > So client socket will be accepted and given to separate thread for read > data from TCP stream. > > Rgds, > > Kamal > > *From:* Alexander Fedulov > *Sent:* 31 October 2023 04:03 PM > *To:* Kamal Mittal > *Cc:* user@flink.apache.org > *Subject:* Re: Flink custom parallel data source > > > > Please note that SourceFunction API is deprecated and is due to be > removed, possibly in the next major version of Flink. > > Ideally you should not be manually spawning threads in your Flink > applications. Typically you would only perform data fetching in the sources > and do processing in the subsequent operators which you can scale > independently from the source parallelism. Can you describe what you are > trying to achieve? > > > > Best, > > Alexander Fedulov > > > > On Tue, 31 Oct 2023 at 07:22, Kamal Mittal via user > wrote: > > Hello Community, > > > > I need to have a custom parallel data source (Flink ParallelSourceFunction) > for fetching data based on some custom logic. In this source function, > opening multiple threads via java thread pool to distribute work further. > > > > These threads share Flink provided ‘SourceContext’ and collect records via > source_context.collect() method. > > > > Is it ok to share source context in separate threads and get data? > > > > Is there any issue for downstream operators due to above design? > > > > Rgds, > > Kamal > >
RE: Flink custom parallel data source
Thanks for sharing views. Our client supports TCP stream based traffic only which is in some proprietary format and need to decode that. System which is accepting this traffic is flink based and that’s why all this tried with custom data source? As you suggested message broker below then how it is feasible in this case? From: Alexander Fedulov Sent: 01 November 2023 01:54 AM To: Kamal Mittal Cc: user@flink.apache.org Subject: Re: Flink custom parallel data source Flink natively supports a pull-based model for sources, where the source operators request data from the external system when they are ready to process it. Implementing a TCP server socket operator essentially creates a push-based source, which could lead to backpressure problems if the data ingestion rate exceeds the processing rate. You also lose any delivery guarantees because Flink's fault tolerance model relies on having replayable sources. Is using a message broker not feasible in your case? Best, Alexander Fedulov On Tue, 31 Oct 2023 at 13:08, Kamal Mittal mailto:kamal.mit...@ericsson.com>> wrote: Hello, We are writing TCP server socket custom source function in which TCP server socket listener will accept connections and read data. Single Custom source server socket function – ServerSocket serversocket = new ServerSocket(); Now using thread pool accept multiple connections in separate threads = new Runnable () -> serversocket.accept(); So client socket will be accepted and given to separate thread for read data from TCP stream. Rgds, Kamal From: Alexander Fedulov mailto:alexander.fedu...@gmail.com>> Sent: 31 October 2023 04:03 PM To: Kamal Mittal mailto:kamal.mit...@ericsson.com>> Cc: user@flink.apache.org<mailto:user@flink.apache.org> Subject: Re: Flink custom parallel data source Please note that SourceFunction API is deprecated and is due to be removed, possibly in the next major version of Flink. Ideally you should not be manually spawning threads in your Flink applications. Typically you would only perform data fetching in the sources and do processing in the subsequent operators which you can scale independently from the source parallelism. Can you describe what you are trying to achieve? Best, Alexander Fedulov On Tue, 31 Oct 2023 at 07:22, Kamal Mittal via user mailto:user@flink.apache.org>> wrote: Hello Community, I need to have a custom parallel data source (Flink ParallelSourceFunction) for fetching data based on some custom logic. In this source function, opening multiple threads via java thread pool to distribute work further. These threads share Flink provided ‘SourceContext’ and collect records via source_context.collect() method. Is it ok to share source context in separate threads and get data? Is there any issue for downstream operators due to above design? Rgds, Kamal
Re: Flink custom parallel data source
> As you suggested message broker below then how it is feasible in this case? To my mind, the idea would be to use something like a socket source for Kafka Connect. This would give you a simple, reliable way to get the data stored into a replayable data store. You'd then be able to start, stop, and redeploy the Flink app without worrying about data loss because the data reception and storage would be decoupled from the data processing. David On Tue, Oct 31, 2023 at 7:50 PM Kamal Mittal via user wrote: > > Thanks for sharing views. > > > > Our client supports TCP stream based traffic only which is in some proprietary format and need to decode that. System which is accepting this traffic is flink based and that’s why all this tried with custom data source? > > > > As you suggested message broker below then how it is feasible in this case? > > > > From: Alexander Fedulov > Sent: 01 November 2023 01:54 AM > To: Kamal Mittal > Cc: user@flink.apache.org > Subject: Re: Flink custom parallel data source > > > > Flink natively supports a pull-based model for sources, where the source operators request data from the external system when they are ready to process it. Implementing a TCP server socket operator essentially creates a push-based source, which could lead to backpressure problems if the data ingestion rate exceeds the processing rate. You also lose any delivery guarantees because Flink's fault tolerance model relies on having replayable sources. > > Is using a message broker not feasible in your case? > > Best, > > Alexander Fedulov > > > > On Tue, 31 Oct 2023 at 13:08, Kamal Mittal wrote: > > Hello, > > > > We are writing TCP server socket custom source function in which TCP server socket listener will accept connections and read data. > > Single Custom source server socket function – ServerSocket serversocket = new ServerSocket(); > > Now using thread pool accept multiple connections in separate threads = new Runnable () -> serversocket.accept(); > > So client socket will be accepted and given to separate thread for read data from TCP stream. > > Rgds, > > Kamal > > From: Alexander Fedulov > Sent: 31 October 2023 04:03 PM > To: Kamal Mittal > Cc: user@flink.apache.org > Subject: Re: Flink custom parallel data source > > > > Please note that SourceFunction API is deprecated and is due to be removed, possibly in the next major version of Flink. > > Ideally you should not be manually spawning threads in your Flink applications. Typically you would only perform data fetching in the sources and do processing in the subsequent operators which you can scale independently from the source parallelism. Can you describe what you are trying to achieve? > > > > Best, > > Alexander Fedulov > > > > On Tue, 31 Oct 2023 at 07:22, Kamal Mittal via user wrote: > > Hello Community, > > > > I need to have a custom parallel data source (Flink ParallelSourceFunction) for fetching data based on some custom logic. In this source function, opening multiple threads via java thread pool to distribute work further. > > > > These threads share Flink provided ‘SourceContext’ and collect records via source_context.collect() method. > > > > Is it ok to share source context in separate threads and get data? > > > > Is there any issue for downstream operators due to above design? > > > > Rgds, > > Kamal >