Hey there, we are adding a small change to the KIP-447 public API. The default value of `transaction.abort.timed.out.transaction.cleanup.interval.ms` shall be changed from 1 minute to 10 seconds. The goal here is to trigger the expired transaction more frequently in order to reduce the consumer pending offset fetch wait time.
Let me know if you have further questions, thanks! On Wed, Jan 8, 2020 at 3:44 PM Boyang Chen <reluctanthero...@gmail.com> wrote: > Thanks Guozhang for another review! I have addressed all the javadoc > changes for PendingTransactionException in the KIP. For FENCED_INSTANCE_ID > the only thrown place would be on the new send offsets API, which is also > addressed. > > Thanks Matthias for the vote! As we have 3 binding votes (Guozhang, Jason, > and Matthias), the KIP is officially accepted and prepared to ship in 2.5. > > Still feel free to put more thoughts on either discussion or voting thread > to refine the KIP! > > > On Wed, Jan 8, 2020 at 3:15 PM Matthias J. Sax <matth...@confluent.io> > wrote: > >> I just re-read the KIP. Overall I am +1 as well. >> > >> Some minor comments (also apply to the Google design doc): >> >> 1) As 2.4 was release, references should be updated to 2.5. >> >> Addressed > >> >> >>> 2) About the upgrade path, the KIP says: >> >> 2a) >> >> > Broker must be upgraded to 2.4 first. This means the >> `inter.broker.protocol.version` (IBP) has to be set to the latest. Any >> produce request with higher version will automatically get fenced because >> of no support. >> >> From my understanding, this is not correct? After a broker is updated to >> the new binaries, it should accept new requests, even if IBP was not >> bumped yet? >> >> Your understanding was correct, after some offline discussion we should > not worry about IBP in this case. > >> 2b) >> >> About the two rolling bounces for KS apps and the statement >> >> > one should never allow task producer and thread producer under the same >> application group >> >> In the second rolling bounce, we might actually mix both (ie, per-task >> and per-thread producers) but this is fine as explained in the KIP. The >> only case we cannot allow is, old per-task producers (without consumer >> generation fencing) to be mixed with per-thread producers (that rely >> solely on consumer generation fencing). >> >> Does this sound correct? >> >> Correct, that's the purpose of doing 2 rolling bounce, where the first > one is to guarantee everyone's opt-in for generation fencing. > >> >> 3) We should also document how users can use KS 2.5 applications against >> older brokers -- for this case, we need to stay on per-task producers >> and cannot use the new fencing mechanism. Currently, the KIP only >> describe a single way how users could make this work: by setting (and >> keeping) UPGRADE_FROM config to 2.4 (what might not be an ideal solution >> and might also not be clear by itself that people would need to do this)? >> >> >> Yes exactly, at the moment we are actively working on a plan to acquire > broker's IBP during stream start-up and initialize based off that > information, > so that user doesn't need to keep UPGRADE_FROM simply for working with old > brokers. > >> >> -Matthias >> >> >> >> On 9/18/19 4:41 PM, Boyang Chen wrote: >> > Bump this thread to see if someone could also review! >> > >> > On Mon, Sep 9, 2019 at 5:00 PM Boyang Chen <reluctanthero...@gmail.com> >> > wrote: >> > >> >> Thank you Jason! Addressed the comments. >> >> >> >> Thank you Guozhang for explaining. I will document the timeout setting >> >> reasoning in the design doc. >> >> >> >> >> >> On Mon, Sep 9, 2019 at 1:49 PM Guozhang Wang <wangg...@gmail.com> >> wrote: >> >> >> >>> On Fri, Sep 6, 2019 at 6:33 PM Boyang Chen < >> reluctanthero...@gmail.com> >> >>> wrote: >> >>> >> >>>> Thanks Guozhang, I have polished the design doc to make it sync with >> >>>> current KIP. As for overriding default timeout values, I guess it's >> >>> already >> >>>> stated in the KIP to set txn timeout to 10s, are you suggesting we >> >>> should >> >>>> also put down this recommendation on the KIP for non-stream EOS >> users? >> >>>> >> >>>> My comment is not for changing any produce / consumer default config >> >>> values, but for the Streams configs, to make sure that our >> >>> overridden config values respect the above rules. That is, we check >> the >> >>> actual value used in the config if they are ever overridden by users, >> and >> >>> if the above were not true we can log a warning that it may be risky >> to >> >>> encounter some unnecessary rebalances. >> >>> >> >>> Again, this is not something we need to include in the KIP since it >> is not >> >>> part of public APIs, just to emphasize that the internal >> implementation >> >>> can >> >>> have some safety guard like this. >> >>> >> >>> Guozhang >> >>> >> >>> >> >>> >> >>>> Boyang >> >>>> >> >>>> On Thu, Sep 5, 2019 at 8:43 PM Guozhang Wang <wangg...@gmail.com> >> >>> wrote: >> >>>> >> >>>>> Hello Boyang, >> >>>>> >> >>>>> Just realized one thing about timeout configurations that we should >> >>>>> consider including in this KIP as well: >> >>>>> >> >>>>> 1) In Producer we have: max.block.ms (default value 60sec), >> >>>>> request.timeout >> >>>>> (30sec), delivery.timeout.ms (120sec), transaction.timeout (60sec) >> >>>>> 2) In Consumer we have: session.timeout (10sec), request.timeout >> >>> (30sec), >> >>>>> default.api.timeout.ms (60sec). >> >>>>> >> >>>>> Within a transaction (i.e. after we've beginTxn), we could >> potentially >> >>>> call >> >>>>> consumer blocking APIs that depend on default.api.timeout.ms, and >> >>> call >> >>>>> producer blocking APIs that depend on max.block.ms. Also, if the >> >>> user is >> >>>>> following a consumer->producer pattern, then it could be kicked and >> >>>> fenced >> >>>>> either by txn or by consumer group session. >> >>>>> >> >>>>> So we want to make sure that in the caller, e.g. Kafka Streams: >> >>>>> >> >>>>> 1) transaction.timeout < max.block.ms >> >>>>> 2) transaction.timeout < delivery.timeout.ms >> >>>>> 3) transaction.timeout < default.api.timeout.ms >> >>>>> 4) transaction.timeout ~= default.api.timeout.ms (I think this is >> >>>> already >> >>>>> mentioned in the KIP, just wanted to bring this up again) >> >>>>> >> >>>>> We do not need to override the default since not every users are >> >>>> following >> >>>>> the consumer -> producer pattern, but in cases like Streams where it >> >>> is >> >>>>> indeed the case, we should override the default values to obey the >> >>> above >> >>>>> rules. >> >>>>> >> >>>>> Guozhang >> >>>>> >> >>>>> >> >>>>> >> >>>>> On Thu, Sep 5, 2019 at 5:47 PM Guozhang Wang <wangg...@gmail.com> >> >>> wrote: >> >>>>> >> >>>>>> Thanks Boyang, I'm +1 on the KIP. >> >>>>>> >> >>>>>> Could you also update the detailed design doc >> >>>>>> >> >>>>> >> >>>> >> >>> >> https://docs.google.com/document/d/1LhzHGeX7_Lay4xvrEXxfciuDWATjpUXQhrEIkph9qRE/edit >> >>>>> which >> >>>>>> seems a bit out-dated with the latest proposal? >> >>>>>> >> >>>>>> >> >>>>>> Guozhang >> >>>>>> >> >>>>>> On Wed, Sep 4, 2019 at 10:45 AM Boyang Chen < >> >>>> reluctanthero...@gmail.com> >> >>>>>> wrote: >> >>>>>> >> >>>>>>> Hey all, >> >>>>>>> >> >>>>>>> I would like to start the vote for KIP-447 >> >>>>>>> < >> >>>>>>> >> >>>>> >> >>>> >> >>> >> https://cwiki.apache.org/confluence/display/KAFKA/KIP-447%3A+Producer+scalability+for+exactly+once+semantics >> >>>>>>>> . >> >>>>>>> This is a very important step to improve Kafka Streams scalability >> >>> in >> >>>>>>> exactly-once semantics, by avoiding linearly increasing number of >> >>>>>>> producers >> >>>>>>> with topic partition increases. >> >>>>>>> >> >>>>>>> Thanks, >> >>>>>>> Boyang >> >>>>>>> >> >>>>>> >> >>>>>> >> >>>>>> -- >> >>>>>> -- Guozhang >> >>>>>> >> >>>>> >> >>>>> >> >>>>> -- >> >>>>> -- Guozhang >> >>>>> >> >>>> >> >>> >> >>> >> >>> -- >> >>> -- Guozhang >> >>> >> >> >> > >> >>
