Re: Flink Kafka consumer with low latency requirement

2019-06-24 Thread xwang355
I posted my related observation here in a separated thread. http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/Does-making-synchronize-call-might-choke-the-whole-pipeline-tc28383.html -- Sent from: http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/

Re: Flink Kafka consumer with low latency requirement

2019-06-24 Thread xwang355
private static void doWork(long tid) throws InterruptedException { if (!sortedTid.contains(tid)) { sortedTid.add(tid); } // simulate a straggler, make the thread with the lowest tid a slow processor if (

Re: Flink Kafka consumer with low latency requirement

2019-06-24 Thread Fabian Hueske
Hi, What kind of function do you use to implement the operator that has the blocking call? Did you have a look at the AsyncIO operator? It was designed for exactly such use cases. It issues multiple asynchronous requests to an external service and waits for the response. Best, Fabian Am Mo., 24.

Re: Flink Kafka consumer with low latency requirement

2019-06-24 Thread xwang355
Fabian, Does the above stack trace looks like a deadlock? at org.apache.flink.runtime.io.network.partition.consumer.SingleInputGate.getNextBufferOrEvent(SingleInputGate.java:539) - locked <0x0007baf84040> (a java.util.ArrayDeque) at org.apache.flink.runtime.io.netwo

Re: Flink Kafka consumer with low latency requirement

2019-06-24 Thread xwang355
Fabian, Thank you for replying. If I understand your previous comment correctly, I setup up a consumer with parallelism 1 and connect a worker task with parallelism 2. If worker thread one is making a block call and stuck for 60s, the consumer thread should continue fetching from the partition

Re: Flink Kafka consumer with low latency requirement

2019-06-24 Thread Fabian Hueske
Hi Ben, Flink's Kafka consumers track their progress independent of any worker. They keep track of the reading offset for themselves (committing progress to Kafka is optional and only necessary to have progress monitoring in Kafka's metrics). As soon as a consumer reads and forwards an event, it i

Flink Kafka consumer with low latency requirement

2019-06-20 Thread wang xuchen
Dear Flink experts, I am experimenting Flink for a use case where there is a tight latency requirements. A stackoverflow article suggests that I can use setParallism(n) to process a Kafka partition in a multi-threaded way. My understanding is there is still one kafka consumer per partition, but b