Hey Vinay, Did you forget to attach the simple class?
-Jason On Thu, Apr 28, 2016 at 1:14 PM, vinay sharma <vinsharma.t...@gmail.com> wrote: > I was also wondering that if commitSync acts as heartbeat then why do we > still trigger heartbeat request on commit? why not just reset its time on > successful commitSync? or am i wrong and we do this already? > > Regards, > Vinay > > On Thu, Apr 28, 2016 at 3:38 PM, vinay sharma <vinsharma.t...@gmail.com> > wrote: > > > Hi Jason, > > > > Attached is a simple class with a main method. I used this for > reproducing > > issue and generate logs that i attached earlier. This class has code > > snippets of poller relevant to the issue. > > > > Regards, > > Vinay Sharma > > > > On Thu, Apr 28, 2016 at 3:30 PM, Jason Gustafson <ja...@confluent.io> > > wrote: > > > >> Hey Vinay, > >> > >> Thanks, that's really helpful. It does seem like there might be a > problem > >> with the heartbeat trigger logic. I'll see if I can reproduce what > you're > >> seeing locally. Might be helpful if you share a snippet of your poll > loop. > >> > >> Thanks, > >> Jason > >> > >> On Thu, Apr 28, 2016 at 11:55 AM, vinay sharma < > vinsharma.t...@gmail.com> > >> wrote: > >> > >> > Hi Jason, > >> > > >> > i reverted back to KAFKA-3149. Producer still had issues related to > >> schema > >> > but my consumer worked. > >> > > >> > Now consumer worked as expected. Although i did not encountered an > error > >> > and generation was not marked dead by coordinator but i still see that > >> > successful heartbeat response are not logged as expected. > >> > My observation is following:- > >> > 1) Meta refresh also triggers heartbeat request. I say this because > >> > sometimes i see 2 heartbeat responses logged just a few milliseconds > >> away > >> > where meta refresh and proactive commit happened almost > simultaneously. > >> > 2) I still see that some commitSync requests do not have a heartbeat > >> > logged before or after commit. Although next proactive commit happened > >> just > >> > in time and this time heartbeat request was successful hence saved > >> session. > >> > In attached log you can see that poll was done at 14:17:41, a commit > >> > happened at 14:17:56 and another commit happened at 14:18:14. The only > >> > heart beat response logged during this time is at 14:18:14 which is 29 > >> > seconds after poll where as a commit was performed 15 seconds after > >> poll. > >> > Heartbeat interval was 3000. > >> > 3) There are long pauses in heartbeat responses in logs which should > >> cause > >> > session to timeout but its not happening. This implies that commits > >> trigger > >> > a heartbeat but they also act as heartbeat. > >> > > >> > > >> > Regards, > >> > Vinay > >> > > >> > > >> > On Thu, Apr 28, 2016 at 12:29 PM, Jason Gustafson <ja...@confluent.io > > > >> > wrote: > >> > > >> >> Ah, yeah. That's probably caused by the new topic metadata version, > >> which > >> >> isn't supported on 0.9 brokers. To test on trunk, you'd have to > upgrade > >> >> the > >> >> brokers as well. Either that or you can rewind to before KAFKA-3306 > >> (which > >> >> was just committed the day before yesterday)? > >> >> > >> >> -Jason > >> >> > >> >> On Thu, Apr 28, 2016 at 9:01 AM, vinay sharma < > >> vinsharma.t...@gmail.com> > >> >> wrote: > >> >> > >> >> > Hi Jason, > >> >> > > >> >> > I build kafka-client and tried using it but my producers and > >> consumers > >> >> > started throwing below exception. Is 0.10 not going to be > compatible > >> >> with > >> >> > brokers on version 0.9.0.1? or do i need to make some config > changes > >> to > >> >> > producers / consumers to make them compatible with brokers on old > >> >> version? > >> >> > or do i need to upgrade brokers to new version as well? > >> >> > > >> >> > org.apache.kafka.common.protocol.types.SchemaException: Error > >> reading > >> >> > field 'brokers': Error reading field 'host': Error reading string > of > >> >> length > >> >> > 17995, only 145 bytes available > >> >> > at > org.apache.kafka.common.protocol.types.Schema.read(Schema.java:75) > >> >> > at > >> >> > > >> >> > > >> >> > >> > org.apache.kafka.clients.NetworkClient.parseResponse(NetworkClient.java:380) > >> >> > at > >> >> > > >> >> > > >> >> > >> > org.apache.kafka.clients.NetworkClient.handleCompletedReceives(NetworkClient.java:449) > >> >> > > >> >> > Regards, > >> >> > Vinay Sharma > >> >> > > >> >> > On Thu, Apr 28, 2016 at 12:32 AM, Jason Gustafson < > >> ja...@confluent.io> > >> >> > wrote: > >> >> > > >> >> > > Hey Vinay, > >> >> > > > >> >> > > Any chance you can run the same test against trunk? I'm guessing > >> this > >> >> > might > >> >> > > be caused by a bug in the 0.9 consumer which basically causes > some > >> >> > requests > >> >> > > to fail when a bunch of them are sent to the broker at the same > >> time. > >> >> > > > >> >> > > -Jason > >> >> > > > >> >> > > On Wed, Apr 27, 2016 at 1:02 PM, vinay sharma < > >> >> vinsharma.t...@gmail.com> > >> >> > > wrote: > >> >> > > > >> >> > > > Hi Jason, > >> >> > > > > >> >> > > > This makes sense.We use 0.9.0.1 and we do have session timeout > >> set a > >> >> > bit > >> >> > > > high but nothing can guarantee that there will be no case when > >> >> > processing > >> >> > > > may not go higher than session timeout. I am trying to test a > >> >> proactive > >> >> > > > commit approach to handle such cases when processing takes > >> unusually > >> >> > long > >> >> > > > time. To keep consumer's session alive during long processing > >> time i > >> >> > > > proactively commitSync processed records every 15 seconds. > >> Session > >> >> > > timeout > >> >> > > > i kept is 30000. > >> >> > > > > >> >> > > > *Problem:-* > >> >> > > > With heart beat interval is 3000 then i expect a hearbeat > request > >> >> to be > >> >> > > > sent on each proactive commit which happens every 15 seconds. > In > >> my > >> >> > > tests i > >> >> > > > see that this does not happen always. I see a time window which > >> is > >> >> > > greater > >> >> > > > than 30 seconds where no hearbeat is sent even thought there > were > >> >> > commits > >> >> > > > in this duration. After this window i see a couple of > successful > >> >> > > heartbeat > >> >> > > > responses till the end of poll but as soon as i poll again and > >> call > >> >> > > > commitSync in next poll i get "ILLEGAL_GENERATION" error. This > >> error > >> >> > > always > >> >> > > > happen just after meta refresh or in next poll processing > after a > >> >> meta > >> >> > > > refresh. I am attaching logs where i kept meta refresh interval > >> >> 40000, > >> >> > > > 90000, 500000. > >> >> > > > > >> >> > > > *Test results *:- > >> >> > > > Test with meta refresh 40000 ms ran around 70 seconds from 1st > >> poll. > >> >> > > > Test with meta refresh 90000 ms ran around 120 seconds from 1st > >> >> poll. > >> >> > > > Test with meta refresh 500000 ms ran around 564 seconds from > 1st > >> >> poll. > >> >> > > > > >> >> > > > Every test falls in line with above test cases where generation > >> is > >> >> > marked > >> >> > > > dead some time after a meta refresh. Meta refresh before 1st > poll > >> >> does > >> >> > > not > >> >> > > > create any issue but the ones after poll and during long > >> processing > >> >> do. > >> >> > > > > >> >> > > > *Environment:-* > >> >> > > > My setup has 3 brokers 1 zk. Topic has 3 partitions ans has > >> >> replication > >> >> > > > factor 3. Messages are already published to topic. > >> >> > > > > >> >> > > > *Logic used in test cases :- * > >> >> > > > On each poll I initialize a map with current committed offset > >> >> position > >> >> > of > >> >> > > > partitions being consumed. I update this map after each record > >> >> > processing > >> >> > > > and use this map to proactively commit every 15 seconds. Map is > >> >> > > initialized > >> >> > > > again after a proactive commit. > >> >> > > > > >> >> > > > I am not sure what is wrong here but i do not see any issue in > >> code > >> >> or > >> >> > > > offset commits going on. Log files and a class with main method > >> are > >> >> > > > attached for your reference. > >> >> > > > > >> >> > > > Regards, > >> >> > > > Vinay Sharma > >> >> > > > > >> >> > > > > >> >> > > > > >> >> > > > On Wed, Apr 27, 2016 at 2:46 PM, Jason Gustafson < > >> >> ja...@confluent.io> > >> >> > > > wrote: > >> >> > > > > >> >> > > >> Hi Vinay, > >> >> > > >> > >> >> > > >> Answers below: > >> >> > > >> > >> >> > > >> 1) Is it correct to say that each commitSync will trigger a > >> >> > > >> HeartBeatTask? > >> >> > > >> > If there is no hear beat sent in past since specified > >> heartbeat > >> >> > > interval > >> >> > > >> > then i should see a successful heartbeat response or failure > >> >> message > >> >> > > in > >> >> > > >> > logs near to commitSync success log? > >> >> > > >> > >> >> > > >> > >> >> > > >> Not quite. Heartbeats are sent periodically according to the > >> >> > > >> heartbeat.interval.ms configuration. However, since the > >> consumer > >> >> has > >> >> > no > >> >> > > >> background thread, they can only be sent in API calls such as > >> >> poll() > >> >> > or > >> >> > > >> commitSync(). So calling commitSync() may or may not result > in a > >> >> > > heartbeat > >> >> > > >> depending only on whether one is "due." > >> >> > > >> > >> >> > > >> 2) is it correct to say that Meta Data refresh will not act as > >> >> > > heartbeat, > >> >> > > >> > will not trigger heartBeatTask and will not reset > >> heartBeatTask? > >> >> > > >> > >> >> > > >> > >> >> > > >> That is correct. Metadata refreshes are not related to > >> heartbeats. > >> >> > > >> > >> >> > > >> 3) Where does a consumer session maintained? Lets say my > >> consumer > >> >> is > >> >> > > >> > listening to 3 partitions on a 3 broker cluster where each > >> >> broker is > >> >> > > >> leader > >> >> > > >> > of 1 partition. So will each of the brokers will have a > >> session > >> >> for > >> >> > my > >> >> > > >> > consumer or is it just 1 session maintained somewhere in > >> common > >> >> like > >> >> > > >> > zookeeper? > >> >> > > >> > >> >> > > >> > >> >> > > >> One of the brokers serves as the "group coordinator." When the > >> >> > consumer > >> >> > > >> starts up, it sends a GroupCoordinator request to one of the > >> >> brokers > >> >> > to > >> >> > > >> find out who the coordinator is. Currently, coordinators are > >> chosen > >> >> > from > >> >> > > >> among the leaders of the partitions of the __consumer_offsets > >> >> topic. > >> >> > > This > >> >> > > >> lets us take advantage of the leader election process to also > >> >> handle > >> >> > > >> coordinator failures. The coordinator of each group maintains > >> state > >> >> > for > >> >> > > >> the > >> >> > > >> group and keeps track of session timeouts. > >> >> > > >> > >> >> > > >> 4) In above setup, during a long processing if I commit a > record > >> >> > through > >> >> > > >> > commmitSync which triggers a hear beat request and a > >> successful > >> >> > > >> response is > >> >> > > >> > received for the same then what does this response means? > >> does it > >> >> > mean > >> >> > > >> that > >> >> > > >> > my session with each broker is renewed? or does it mean that > >> just > >> >> > the > >> >> > > >> > leader for partition of committed record knows that my > >> consumer > >> >> is > >> >> > > alive > >> >> > > >> > and consumer's session on other brokers will still timeout? > >> >> > > >> > >> >> > > >> > >> >> > > >> The coordinator is the only broker that is aware of a > consumer's > >> >> > session > >> >> > > >> and all offset commits are sent to it. Successful heartbeats > >> mean > >> >> that > >> >> > > the > >> >> > > >> session is still active. Heartbeats are also used to let the > >> >> consumer > >> >> > > >> discover when a rebalance has begun. If a new member joins the > >> >> group, > >> >> > > then > >> >> > > >> the coordinator returns an error code in the heartbeat > >> responses of > >> >> > the > >> >> > > >> active members to let them know that they need to rejoin the > >> group > >> >> so > >> >> > > that > >> >> > > >> partitions can be rebalanced. > >> >> > > >> > >> >> > > >> I wouldn't get too hung up on commit/heartbeat behavior. The > >> crux > >> >> of > >> >> > the > >> >> > > >> issue is that you need to call poll() often enough to avoid > >> getting > >> >> > > timed > >> >> > > >> out by the coordinator. If you find this happening frequently, > >> you > >> >> > > >> probably > >> >> > > >> need to increase session.timeout.ms. There's not really any > >> >> downside > >> >> > to > >> >> > > >> doing so other than that hard failures (in which the consumer > >> >> can't be > >> >> > > >> shutdown cleanly) will take a little longer to detect. Normal > >> >> shutdown > >> >> > > >> doesn't have this problem. It can be difficult in 0.9 to > ensure > >> >> that > >> >> > > >> poll() > >> >> > > >> is called often enough since you don't have direct control > over > >> the > >> >> > > amount > >> >> > > >> of data returned in poll(), but we're adding an option > >> >> > > (max.poll.records) > >> >> > > >> in 0.10 which hopefully can be set conservatively enough to > make > >> >> this > >> >> > > >> problem go away. > >> >> > > >> > >> >> > > >> -Jason > >> >> > > >> > >> >> > > >> On Wed, Apr 27, 2016 at 7:11 AM, vinay sharma < > >> >> > vinsharma.t...@gmail.com > >> >> > > > > >> >> > > >> wrote: > >> >> > > >> > >> >> > > >> > Hey, > >> >> > > >> > > >> >> > > >> > I am working on a simplified test case to check if there is > >> any > >> >> > issue > >> >> > > >> in my > >> >> > > >> > code. Just to make sure that any of my assumptions are not > >> >> wrong, it > >> >> > > >> will > >> >> > > >> > be great if you can please help me in finding answers to > >> >> following > >> >> > > >> > queries:- > >> >> > > >> > > >> >> > > >> > 1) Is it correct to say that each commitSync will trigger a > >> >> > > >> HeartBeatTask? > >> >> > > >> > If there is no hear beat sent in past since specified > >> heartbeat > >> >> > > interval > >> >> > > >> > then i should see a successful heartbeat response or failure > >> >> message > >> >> > > in > >> >> > > >> > logs near to commitSync success log? > >> >> > > >> > 2) is it correct to say that Meta Data refresh will not act > as > >> >> > > >> heartbeat, > >> >> > > >> > will not trigger heartBeatTask and will not reset > >> heartBeatTask? > >> >> > > >> > 3) Where does a consumer session maintained? Lets say my > >> >> consumer is > >> >> > > >> > listening to 3 partitions on a 3 broker cluster where each > >> >> broker is > >> >> > > >> leader > >> >> > > >> > of 1 partition. So will each of the brokers will have a > >> session > >> >> for > >> >> > my > >> >> > > >> > consumer or is it just 1 session maintained somewhere in > >> common > >> >> like > >> >> > > >> > zookeeper? > >> >> > > >> > 4) In above setup, during a long processing if I commit a > >> record > >> >> > > through > >> >> > > >> > commmitSync which triggers a hear beat request and a > >> successful > >> >> > > >> response is > >> >> > > >> > received for the same then what does this response means? > >> does it > >> >> > mean > >> >> > > >> that > >> >> > > >> > my session with each broker is renewed? or does it mean that > >> just > >> >> > the > >> >> > > >> > leader for partition of committed record knows that my > >> consumer > >> >> is > >> >> > > alive > >> >> > > >> > and consumer's session on other brokers will still timeout? > >> >> > > >> > > >> >> > > >> > Regards, > >> >> > > >> > Vinay Sharma > >> >> > > >> > > >> >> > > >> > On Tue, Apr 26, 2016 at 2:38 PM, Jason Gustafson < > >> >> > ja...@confluent.io> > >> >> > > >> > wrote: > >> >> > > >> > > >> >> > > >> > > Hey Vinay, > >> >> > > >> > > > >> >> > > >> > > Are you saying that heartbeats are not sent while a > metadata > >> >> > refresh > >> >> > > >> is > >> >> > > >> > in > >> >> > > >> > > progress? Do you have any logs which show us the apparent > >> >> problem? > >> >> > > >> > > > >> >> > > >> > > Thanks, > >> >> > > >> > > Jason > >> >> > > >> > > > >> >> > > >> > > On Tue, Apr 26, 2016 at 8:18 AM, vinay sharma < > >> >> > > >> vinsharma.t...@gmail.com> > >> >> > > >> > > wrote: > >> >> > > >> > > > >> >> > > >> > > > Hi Ismael, > >> >> > > >> > > > > >> >> > > >> > > > Treating commitSync as heartbeat will definitely resolve > >> the > >> >> > issue > >> >> > > >> i am > >> >> > > >> > > > facing but the reason behind my issue does not seem to > be > >> >> what > >> >> > > >> > mentioned > >> >> > > >> > > in > >> >> > > >> > > > defect (i.e frequent commitSync requests). > >> >> > > >> > > > > >> >> > > >> > > > I am sending CommitSync periodically only to keep my > >> session > >> >> > alive > >> >> > > >> when > >> >> > > >> > > my > >> >> > > >> > > > consumer is still processing records and is close to > >> session > >> >> > time > >> >> > > >> out > >> >> > > >> > > > (tried 10th / 12th / 15th / 20th second after poll > called > >> >> where > >> >> > > >> session > >> >> > > >> > > > time is 30). I see heartbeat response received in logs > >> along > >> >> > with > >> >> > > >> each > >> >> > > >> > > > commitSync call but this stops after a meta data refresh > >> >> request > >> >> > > is > >> >> > > >> > > issued. > >> >> > > >> > > > I see in logs that commit goes successful but no > heartbeat > >> >> > > response > >> >> > > >> > > > received message in logs after meta refresh till next > >> poll. > >> >> > > >> > > > > >> >> > > >> > > > Regards, > >> >> > > >> > > > Vinay Sharma > >> >> > > >> > > > > >> >> > > >> > > > On Mon, Apr 25, 2016 at 5:06 PM, Ismael Juma < > >> >> ism...@juma.me.uk > >> >> > > > >> >> > > >> > wrote: > >> >> > > >> > > > > >> >> > > >> > > > > Hi Vinay, > >> >> > > >> > > > > > >> >> > > >> > > > > This was fixed via > >> >> > > >> https://issues.apache.org/jira/browse/KAFKA-3470 > >> >> > > >> > > > (will > >> >> > > >> > > > > be part of 0.10.0.0). > >> >> > > >> > > > > > >> >> > > >> > > > > Ismael > >> >> > > >> > > > > > >> >> > > >> > > > > > >> >> > > >> > > > > > >> >> > > >> > > > > On Mon, Apr 25, 2016 at 1:52 PM, vinay sharma < > >> >> > > >> > > vinsharma.t...@gmail.com> > >> >> > > >> > > > > wrote: > >> >> > > >> > > > > > >> >> > > >> > > > > > Hello, > >> >> > > >> > > > > > > >> >> > > >> > > > > > I am using client API 0.9.0.1 and facing an issue. > As > >> >> per my > >> >> > > >> logs > >> >> > > >> > it > >> >> > > >> > > > > seems > >> >> > > >> > > > > > that on each commitSync(Offsets) a heartbeat request > >> is > >> >> sent > >> >> > > but > >> >> > > >> > > after > >> >> > > >> > > > a > >> >> > > >> > > > > > metada refresh request till next poll(), commits do > >> not > >> >> send > >> >> > > any > >> >> > > >> > > > hearbeat > >> >> > > >> > > > > > request. > >> >> > > >> > > > > > > >> >> > > >> > > > > > KafkaConsumers i create sometimes get session time > out > >> >> due > >> >> > to > >> >> > > no > >> >> > > >> > > > hearbeat > >> >> > > >> > > > > > specially during longer processing times. I call > >> >> > > >> > CommitSync(offsets) > >> >> > > >> > > > > after > >> >> > > >> > > > > > regular intervals to keep session alive when > >> processing > >> >> > takes > >> >> > > >> > longer > >> >> > > >> > > > than > >> >> > > >> > > > > > usual. Every thing works fine if commit intervals > are > >> >> very > >> >> > > >> small or > >> >> > > >> > > if > >> >> > > >> > > > i > >> >> > > >> > > > > > commit after each record but if i commit lets say > >> every > >> >> 12 > >> >> > > >> seconds > >> >> > > >> > > and > >> >> > > >> > > > 30 > >> >> > > >> > > > > > seconds is session time then i can see consumer > >> getting > >> >> > timed > >> >> > > >> out > >> >> > > >> > > > > > sometimes. > >> >> > > >> > > > > > > >> >> > > >> > > > > > Any help or pointers will be much appreciated. > Thanks > >> in > >> >> > > >> advance. > >> >> > > >> > > > > > > >> >> > > >> > > > > > Regards, > >> >> > > >> > > > > > Vinay sharma > >> >> > > >> > > > > > > >> >> > > >> > > > > > >> >> > > >> > > > > >> >> > > >> > > > >> >> > > >> > > >> >> > > >> > >> >> > > > > >> >> > > > > >> >> > > > >> >> > > >> >> > >> > > >> > > >> > > > > >
