Hi, Sorry for the long delay in replying.
As for your questions: No we are not using SSL. The problem went away for Martin when he was running against his kafka instance locally on his development machine, but we are still seeing the issue when we run it in our testing environment, where the broker is on a remote machine. The network in our testing environment seems stable, from the measurements I have made so far. *Rune Tor* Sørensen +45 3172 2097 <+4531722097> LinkedIn <https://www.linkedin.com/in/runets> Twitter <https://twitter.com/Areian> *Copenhagen* Falcon Social H.C. Andersens Blvd. 27 1553 Copenhagen *Budapest* Falcon Social Colabs Startup Center Zrt 1016 Budapest, Krisztina krt. 99 [image: Falcon Social] <https://www.falconsocial.com/?utm_source=Employee%20emails&utm_medium=email&utm_content=Rune%20Tor&utm_campaign=Mail%20signature> Social Media Management for Enterprise On Tue, Dec 1, 2015 at 11:56 PM, Jason Gustafson <ja...@confluent.io> wrote: > I've been unable to reproduce this issue running locally. Even with a poll > timeout of 1 millisecond, it seems to work as expected. It would be helpful > to know a little more about your setup. Are you using SSL? Are the brokers > remote? Is the network stable? > > Thanks, > Jason > > On Tue, Dec 1, 2015 at 10:06 AM, Jason Gustafson <ja...@confluent.io> > wrote: > > > Hi Martin, > > > > I'm also not sure why the poll timeout would affect this. Perhaps the > > handler is still doing work (e.g. sending requests) when the record set > is > > empty? > > > > As a general rule, I would recommend longer poll timeouts. I've actually > > tended to use Long.MAX_VALUE myself. I'll have a look just to make sure > > everything still works with smaller values though. > > > > -Jason > > > > > > > > On Tue, Dec 1, 2015 at 2:35 AM, Martin Skøtt < > > martin.sko...@falconsocial.com> wrote: > > > >> Hi Jason, > >> > >> That actually sounds like a very plausible explanation. My current > >> consumer > >> is using the default settings, but I have previously used these (taken > >> from > >> the sample in the Javadoc for the new KafkaConsumer): > >> "auto.commit.interval.ms", "1000" > >> "session.timeout.ms", "30000" > >> > >> My consumer loop is quite simple as it just calls a domain specific > >> service: > >> > >> while (true) { > >> ConsumerRecords<String, Object> records = consumer.poll(10000); > >> for (ConsumerRecord<String, Object> record : records) { > >> serve.handle(record.topic(), record.value()); > >> } > >> } > >> > >> The domain service does a number of things (including lookups in a RDBMS > >> and saving to ElasticSearch). In my local test setup a poll will often > >> result between 5.000 and 10.000 records and I can easily see the > >> processing > >> of those taking more than 30 seconds. > >> > >> I'll probably take a look at adding some threading to my consumer and > add > >> more partitions to my topics. > >> > >> That is all fine, but it doesn't really explain why increasing poll > >> timeout > >> made the problem go away :-/ > >> > >> Martin > >> > >> On 30 November 2015 at 19:30, Jason Gustafson <ja...@confluent.io> > wrote: > >> > >> > Hey Martin, > >> > > >> > At a glance, it looks like your consumer's session timeout is > expiring. > >> > This shouldn't happen unless there is a delay between successive calls > >> to > >> > poll which is longer than the session timeout. It might help if you > >> include > >> > a snippet of your poll loop and your configuration (i.e. any > overridden > >> > settings). > >> > > >> > -Jason > >> > > >> > On Mon, Nov 30, 2015 at 8:12 AM, Martin Skøtt < > >> > martin.sko...@falconsocial.com> wrote: > >> > > >> > > Well, I made the problem go away, but I'm not sure why it works :-/ > >> > > > >> > > Previously I used a time out value of 100 for Consumer.poll(). > >> Increasing > >> > > it to 10.000 makes the problem go away completely?! I tried other > >> values > >> > as > >> > > well: > >> > > - 0 problem remained > >> > > - 3000, same as heartbeat.interval, problem remained, but less > >> > frequent > >> > > > >> > > Not really sure what is going on, but happy that the problem went > away > >> > :-) > >> > > > >> > > Martin > >> > > > >> > > On 30 November 2015 at 15:33, Martin Skøtt < > >> > martin.sko...@falconsocial.com > >> > > > > >> > > wrote: > >> > > > >> > > > Hi Guozhang, > >> > > > > >> > > > I have done some testing with various values of > >> heartbeat.interval.ms > >> > > and > >> > > > they don't seem to have any influence on the error messages. > Running > >> > > > kafka-consumer-groups also continues to return that the consumer > >> groups > >> > > > does not exists or is rebalancing. Do you have any suggestions to > >> how I > >> > > > could debug this further? > >> > > > > >> > > > Regards, > >> > > > Martin > >> > > > > >> > > > > >> > > > On 25 November 2015 at 18:37, Guozhang Wang <wangg...@gmail.com> > >> > wrote: > >> > > > > >> > > >> Hello Martin, > >> > > >> > >> > > >> It seems your consumer's heartbeat.interval.ms config value is > too > >> > > small > >> > > >> (default is 3 seconds) for your environment, consider increasing > it > >> > and > >> > > >> see > >> > > >> if this issue goes away. > >> > > >> > >> > > >> At the same time, we have some better error handling fixes in > trunk > >> > > which > >> > > >> will be included in the next point release. > >> > > >> > >> > > >> https://issues.apache.org/jira/browse/KAFKA-2860 > >> > > >> > >> > > >> Guozhang > >> > > >> > >> > > >> > >> > > >> > >> > > >> On Wed, Nov 25, 2015 at 6:54 AM, Martin Skøtt < > >> > > >> martin.sko...@falconsocial.com> wrote: > >> > > >> > >> > > >> > Hi, > >> > > >> > > >> > > >> > I'm experiencing some very strange issues with 0.9. I get these > >> log > >> > > >> > messages from the new consumer: > >> > > >> > > >> > > >> > [main] ERROR > >> > > >> > > org.apache.kafka.clients.consumer.internals.ConsumerCoordinator - > >> > > Error > >> > > >> > ILLEGAL_GENERATION occurred while committing offsets for group > >> > > >> > aaa-bbb-reader > >> > > >> > [main] WARN > >> > > >> org.apache.kafka.clients.consumer.internals.ConsumerCoordinator > >> > > >> > - Auto offset commit failed: Commit cannot be completed due to > >> group > >> > > >> > rebalance > >> > > >> > [main] ERROR > >> > > >> > > org.apache.kafka.clients.consumer.internals.ConsumerCoordinator - > >> > > Error > >> > > >> > ILLEGAL_GENERATION occurred while committing offsets for group > >> > > >> > aaa-bbb-reader > >> > > >> > [main] WARN > >> > > >> org.apache.kafka.clients.consumer.internals.ConsumerCoordinator > >> > > >> > - Auto offset commit failed: > >> > > >> > [main] INFO > >> > > >> org.apache.kafka.clients.consumer.internals.AbstractCoordinator > >> > > >> > - Attempt to join group aaa-bbb-reader failed due to unknown > >> member > >> > > id, > >> > > >> > resetting and retrying. > >> > > >> > > >> > > >> > And this in the broker log: > >> > > >> > [2015-11-25 15:41:01,542] INFO [GroupCoordinator 0]: Preparing > to > >> > > >> > restabilize group aaa-bbb-reader with old generation 1 > >> > > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > [2015-11-25 15:41:01,544] INFO [GroupCoordinator 0]: > >> > > >> > Group aaa-bbb-reader generation 1 is dead and removed > >> > > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > [2015-11-25 15:41:13,474] INFO [GroupCoordinator 0]: Preparing > to > >> > > >> > restabilize group aaa-bbb-reader with old generation 0 > >> > > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > [2015-11-25 15:41:13,475] INFO [GroupCoordinator 0]: Stabilized > >> > > >> > group aaa-bbb-reader generation 1 > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > [2015-11-25 15:41:13,477] INFO [GroupCoordinator 0]: Assignment > >> > > received > >> > > >> > from leader for group aaa-bbb-reader for generation 1 > >> > > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > [2015-11-25 15:41:43,478] INFO [GroupCoordinator 0]: Preparing > to > >> > > >> > restabilize group aaa-bbb-reader with old generation 1 > >> > > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > [2015-11-25 15:41:43,478] INFO [GroupCoordinator 0]: > >> > > >> > Group aaa-bbb-reader generation 1 is dead and removed > >> > > >> > (kafka.coordinator.GroupCoordinator) > >> > > >> > > >> > > >> > When this happens the kafka-consumer-groups describe command > >> keeps > >> > > >> saying > >> > > >> > that the group no longer exists or is rebalancing. What is > >> probably > >> > > even > >> > > >> > worse is that my consumers appears to be looping constantly > >> through > >> > > >> > everything written to the topics!? > >> > > >> > > >> > > >> > Does anyone have any input on what might be happening? > >> > > >> > > >> > > >> > I'm running 0.9 locally on my laptop using one Zookeeper and > one > >> > > broker, > >> > > >> > both using the configuration provided in the distribution. I > >> have 13 > >> > > >> topics > >> > > >> > with two partitions each and a replication factor of 1. I run > one > >> > > >> producer > >> > > >> > and once consumer also on the same machine. > >> > > >> > > >> > > >> > -- > >> > > >> > Martin Skøtt > >> > > >> > > >> > > >> > >> > > >> > >> > > >> > >> > > >> -- > >> > > >> -- Guozhang > >> > > >> > >> > > > > >> > > > > >> > > > >> > > >> > > > > >
