Indeed it is.
Oleg
> On May 4, 2016, at 10:54 AM, Paolo Patierno <ppatie...@live.com> wrote:
>
> It's sad that after almost one month it's still "unassigned" :-(
>
> Paolo PatiernoSenior Software Engineer (IoT) @ Red Hat
> Microsoft MVP on Windows Embedded & IoTMicrosoft Azure Advisor
> Twitter : @ppatierno
> Linkedin : paolopatierno
> Blog : DevExperience
>
>> Subject: Re: KafkaProducer block on send
>> From: ozhurakou...@hortonworks.com
>> To: users@kafka.apache.org
>> Date: Wed, 4 May 2016 14:47:25 +0000
>>
>> Sure
>>
>> Here are both:
>> https://issues.apache.org/jira/browse/KAFKA-3539
>> https://issues.apache.org/jira/browse/KAFKA-3540
>>
>> On May 4, 2016, at 3:24 AM, Paolo Patierno
>> <ppatie...@live.com<mailto:ppatie...@live.com>> wrote:
>>
>> Hi Oleg,
>>
>> can you share the JIRA link here because I totally agree with you.
>> For me the send() should be totally asynchronous and not blocking for the
>> max.block.ms timeout.
>>
>> Currently I'm using the overload with callback that, of course, isn't called
>> if the send() fails due to timeout.
>> In order to catch this scenario I need to do the following :
>>
>> Future<RecordMetadata> future = this.producer.send(....);
>>
>> if (future.isDone()) {
>> try {
>> future.get();
>> } catch (InterruptedException e) {
>> // TODO Auto-generated catch block
>> e.printStackTrace();
>> } catch (ExecutionException e) {
>> // TODO Auto-generated catch block
>> e.printStackTrace();
>> }
>> }
>>
>> I don't like it so much ...
>>
>> Thanks,
>> Paolo.
>>
>> Paolo PatiernoSenior Software Engineer (IoT) @ Red Hat
>> Microsoft MVP on Windows Embedded & IoTMicrosoft Azure Advisor
>> Twitter : @ppatierno
>> Linkedin : paolopatierno
>> Blog : DevExperience
>>
>> Subject: Re: KafkaProducer block on send
>> From: ozhurakou...@hortonworks.com<mailto:ozhurakou...@hortonworks.com>
>> To: users@kafka.apache.org<mailto:users@kafka.apache.org>
>> Date: Mon, 11 Apr 2016 19:42:17 +0000
>>
>> Dana
>>
>> Thanks for the explanation, but it sounds more like a workaround since
>> everything you describe could be encapsulated within the Future itself.
>> After all it "represents the result of an asynchronous computation"
>>
>> executor.submit(new Callable<RecordMetadata>() {
>> @Override
>> public RecordMetadata call() throws Exception {
>> // first make sure the metadata for the topic is available
>> long waitedOnMetadataMs = waitOnMetadata(record.topic(),
>> this.maxBlockTimeMs);
>> . . .
>> }
>> });
>>
>>
>> The above would eliminate the confusion and keep user in control where even
>> a legitimate blockage could be interrupted/canceled etc., based on various
>> business/infrastructure requirements.
>> Anyway, I’ll raise the issue in JIRA and reference this thread
>>
>> Cheers
>> Oleg
>>
>> On Apr 8, 2016, at 10:31 AM, Dana Powers
>> <dana.pow...@gmail.com<mailto:dana.pow...@gmail.com><mailto:dana.pow...@gmail.com>>
>> wrote:
>>
>> The prior discussion explained:
>>
>> (1) The code you point to blocks for a maximum of max.block.ms, which is
>> user configurable. It does not block indefinitely with no user control as
>> you suggest. You are free to configure this to 0 if you like at it will not
>> block at all. Have you tried this like I suggested before?
>>
>> (2) Even if you convinced people to remove waitOnMetadata, the send method
>> *still* blocks on memory back pressure (also configured by max.block.ms).
>> This is for good reason:
>>
>> while True:
>> producer.send(msg)
>>
>> Can quickly devour all of you local memory and crash your process if the
>> outflow rate decreases, say if brokers go down or network partition occurs.
>>
>> -Dana
>> I totally agree with Oleg.
>>
>> As documentation says the producers send data in an asynchronous way and it
>> is enforced by the send method signature with a Future returned.
>> It can't block indefinitely without returning to the caller.
>> I'm mean, you can decide that the code inside the send method blocks
>> indefinitely but in an "asynchronous way", it should first return a Future
>> to the caller that can handle it.
>>
>> Paolo.
>>
>> Paolo PatiernoSenior Software Engineer (IoT) @ Red Hat
>> Microsoft MVP on Windows Embedded & IoTMicrosoft Azure Advisor
>> Twitter : @ppatierno
>> Linkedin : paolopatierno
>> Blog : DevExperience
>>
>> Subject: KafkaProducer block on send
>> From:
>> ozhurakou...@hortonworks.com<mailto:ozhurakou...@hortonworks.com><mailto:ozhurakou...@hortonworks.com>
>> To:
>> users@kafka.apache.org<mailto:users@kafka.apache.org><mailto:users@kafka.apache.org>
>> Date: Thu, 7 Apr 2016 13:04:49 +0000
>>
>> I know it’s been discussed before, but that conversation never really
>> concluded with any reasonable explanation, so I am bringing it up again as
>> I believe this is a bug that would need to be fixed in some future release.
>> Can someone please explain the rational for the following code in
>> KafkaProducer:
>>
>> @Override
>> public Future<RecordMetadata> send(ProducerRecord<K, V> record, Callback
>> callback) {
>> try {
>> // first make sure the metadata for the topic is available
>> long waitedOnMetadataMs = waitOnMetadata(record.topic(),
>> this.maxBlockTimeMs);
>> . . .
>> }
>>
>> By definition the method that returns Future implies that caller decides
>> how long to wait for the completion via Future.get(TIMETOWAIT). In this
>> case there is an explicit blocking call (waitOnMetadata), that can hang
>> infinitely (regardless of the reasons) which essentially results in user’s
>> code deadlock since the Future may never be returned in the first place.
>>
>> Thoughts?
>>
>> Oleg
>>
>>
>>
>>
>
