Hi all, If possible, would a committer please review?
Thanks On Sun, Apr 1, 2018 at 7:24 PM, Richard Yu <yohan.richard...@gmail.com> wrote: > Hi Guozhang, > > I have clarified the KIP a bit to account for Becket's suggestion on > ClientTimeoutException. > About adding an extra config, you were right about my intentions. I am > just wondering if the config > should be included, since Ismael seems to favor an extra configuration, > > Thanks, > Richard > > On Sun, Apr 1, 2018 at 5:35 PM, Guozhang Wang <wangg...@gmail.com> wrote: > >> Hi Richard, >> >> Regarding the streams side changes, we plan to incorporate with the new >> APIs once the KIP is done, which is only internal code changes and hence >> do >> not need to include in the KIP. >> >> Could you update the KIP because it has been quite obsoleted from the >> discussed topics, and I'm a bit loosing track on what is your final >> proposal right now. For example, I'm not completely following your >> "compromise >> of sorts": are you suggesting that we still add overloading functions and >> add a config that will be applied to all overload functions without the >> timeout, while for other overloaded functions with the timeout value the >> config will be ignored? >> >> >> Guozhang >> >> On Fri, Mar 30, 2018 at 8:36 PM, Richard Yu <yohan.richard...@gmail.com> >> wrote: >> >> > On a side note, I have noticed that the several other methods in classes >> > such as StoreChangeLogReader in Streams calls position() which causes >> tests >> > to hang. It might be out of the scope of the KIP, but should I also >> change >> > the methods which use position() as a callback to at the very least >> prevent >> > the tests from hanging? This issue might be out of the KIP, but I >> prefer it >> > if we could at least make my PR pass the Jenkins Q&A. >> > >> > Thanks >> > >> > On Fri, Mar 30, 2018 at 8:24 PM, Richard Yu <yohan.richard...@gmail.com >> > >> > wrote: >> > >> > > Thanks for the review Becket. >> > > >> > > About the methods beginningOffsets(), endOffsets(), ...: >> > > I took a look through the code of KafkaConsumer, but after looking >> > through >> > > the offsetsByTimes() method >> > > and its callbacks in Fetcher, I think these methods already block for >> a >> > > set period of time. I know that there >> > > is a chance that the offsets methods in KafkaConsumer might be like >> poll >> > > (that is one section of the method >> > > honors the timeout while another -- updateFetchPositions -- does not). >> > > However, I don't think that this is the >> > > case with offsetsByTimes since the callbacks that I checked does not >> seem >> > > to hang. >> > > >> > > The clarity of the exception message is a problem. I thought your >> > > suggestion there was reasonable. I included >> > > it in the KIP. >> > > >> > > And on another note, I have noticed that several people has voiced the >> > > opinion that adding a config might >> > > be advisable in relation to adding an extra parameter. I think that we >> > can >> > > have a compromise of sorts: some >> > > methods in KafkaConsumer are relatively similar -- for example, >> > position() >> > > and committed() both call >> > > updateFetchPositions(). I think that we could use the same config for >> > > these method as a default timeout if >> > > the user does not provide one. On the other hand, if they wish to >> specify >> > > a longer or shorter blocking time, >> > > they have the option of changing the timeout. (I included the config >> as >> > an >> > > alternative in the KIP) WDYT? >> > > >> > > Thanks, >> > > Richard >> > > >> > > >> > > On Fri, Mar 30, 2018 at 1:26 AM, Becket Qin <becket....@gmail.com> >> > wrote: >> > > >> > >> Glad to see the KIP, Richard. This has been a really long pending >> issue. >> > >> >> > >> The original arguments from Jay for using config, such as >> max.block.ms, >> > >> instead of using timeout parameters was that people will always hard >> > code >> > >> the timeout, and the hard coded timeout is rarely correct because it >> has >> > >> to >> > >> consider different scenarios. For example, users may receive timeout >> > >> exception when the group coordinator moves. Having a configuration >> with >> > >> some reasonable default value will make users' life easier. >> > >> >> > >> That said, in practice, it seems more useful to have timeout >> parameters. >> > >> We >> > >> have seen some library, using the consumers internally, needs to >> provide >> > >> an >> > >> external flexible timeout interface. Also, user can easily hard code >> a >> > >> value to get the same as a config based solution. >> > >> >> > >> The KIP looks good overall. A few comments: >> > >> >> > >> 1. There are a few other blocking methods that are not included, e.g. >> > >> offsetsForTimes(), beginningOffsets(), endOffsets(). Is there any >> > reason? >> > >> >> > >> 2. I am wondering can we take the KIP as a chance to clean up our >> > timeout >> > >> exception(s)? More specifically, instead of reusing TimeoutException, >> > can >> > >> we introduce a new ClientTimeoutException with different causes, e.g. >> > >> UnknownTopicOrPartition, RequestTimeout, LeaderNotAvailable, etc. >> > >> As of now, the TimeoutException is used in the following three cases: >> > >> >> > >> 1. TimeoutException is a subclass of ApiException which indicates >> the >> > >> exception was returned by the broker. The TimeoutException was >> > >> initially >> > >> returned by the leaders when replication was not done within the >> > >> specified >> > >> timeout in the ProduceRequest. It has an error code of 7, which is >> > >> returned >> > >> by the broker. >> > >> 2. When we migrate to Java clients, in Errors definition, we >> extended >> > >> it >> > >> to indicate request timeout, i.e. a request was sent but the >> response >> > >> was >> > >> not received before timeout. In this case, the clients did not >> have a >> > >> return code from the broker. >> > >> 3. Later at some point, we started to use the TimeoutException for >> > >> clients method call timeout. It is neither related to any broker >> > >> returned >> > >> error code, nor to request timeout on the wire. >> > >> >> > >> Due to the various interpretations, users can easily be confused. As >> an >> > >> example, when a timeout is thrown with "Failed to refresh metadata >> in X >> > >> ms", it is hard to tell what exactly happened. Since we are changing >> the >> > >> API here, it would be good to avoid introducing more ambiguity and >> see >> > >> whether this can be improved. It would be at least one step forward >> to >> > >> remove the usage of case 3. >> > >> >> > >> Thanks, >> > >> >> > >> Jiangjie (Becket) Qin >> > >> >> > >> >> > >> >> > >> >> > >> On Mon, Mar 26, 2018 at 5:50 PM, Guozhang Wang <wangg...@gmail.com> >> > >> wrote: >> > >> >> > >> > @Richard: TimeoutException inherits from RetriableException which >> > >> inherits >> > >> > from ApiException. So users should explicitly try to capture >> > >> > RetriableException in their code and handle the exception. >> > >> > >> > >> > @Isamel, Ewen: I'm trying to push progress forward on this one, >> are we >> > >> now >> > >> > on the same page for using function parameters than configs? >> > >> > >> > >> > >> > >> > Guozhang >> > >> > >> > >> > >> > >> > On Fri, Mar 23, 2018 at 4:42 PM, Ismael Juma <ism...@juma.me.uk> >> > wrote: >> > >> > >> > >> > > Hi Ewen, >> > >> > > >> > >> > > Yeah, I mentioned KAFKA-2391 where some of this was discussed. >> Jay >> > was >> > >> > > against having timeouts in the methods at the time. However, as >> > Jason >> > >> > said >> > >> > > offline, we did end up with a timeout parameter in `poll`. >> > >> > > >> > >> > > Ismael >> > >> > > >> > >> > > On Fri, Mar 23, 2018 at 4:26 PM, Ewen Cheslack-Postava < >> > >> > e...@confluent.io> >> > >> > > wrote: >> > >> > > >> > >> > > > Regarding the flexibility question, has someone tried to dig up >> > the >> > >> > > > discussion of the new consumer APIs when they were being >> written? >> > I >> > >> > > vaguely >> > >> > > > recall these exact questions about using APIs vs configs and >> > >> > flexibility >> > >> > > vs >> > >> > > > bloating the API surface area having already been discussed. >> (Not >> > >> that >> > >> > we >> > >> > > > shouldn't revisit, just that it might also be a faster way to >> get >> > >> to a >> > >> > > full >> > >> > > > understanding of the options, concerns, and tradeoffs). >> > >> > > > >> > >> > > > -Ewen >> > >> > > > >> > >> > > > On Thu, Mar 22, 2018 at 7:19 AM, Richard Yu < >> > >> > yohan.richard...@gmail.com> >> > >> > > > wrote: >> > >> > > > >> > >> > > > > I do have one question though: in the current KIP, throwing >> > >> > > > > TimeoutException to mark >> > >> > > > > that time limit is exceeded is applied to all new methods >> > >> introduced >> > >> > in >> > >> > > > > this proposal. >> > >> > > > > However, how would users respond when a TimeoutException >> (since >> > >> it is >> > >> > > > > considered >> > >> > > > > a RuntimeException)? >> > >> > > > > >> > >> > > > > Thanks, >> > >> > > > > Richard >> > >> > > > > >> > >> > > > > >> > >> > > > > >> > >> > > > > On Mon, Mar 19, 2018 at 6:10 PM, Richard Yu < >> > >> > > yohan.richard...@gmail.com> >> > >> > > > > wrote: >> > >> > > > > >> > >> > > > > > Hi Ismael, >> > >> > > > > > >> > >> > > > > > You have a great point. Since most of the methods in this >> KIP >> > >> have >> > >> > > > > similar >> > >> > > > > > callbacks (position() and committed() both use >> > >> > > fetchCommittedOffsets(), >> > >> > > > > > and >> > >> > > > > > commitSync() is similar to position(), except just updating >> > >> > offsets), >> > >> > > > the >> > >> > > > > > amount of time >> > >> > > > > > they block should be also about equal. >> > >> > > > > > >> > >> > > > > > However, I think that we need to take into account a >> couple of >> > >> > > things. >> > >> > > > > For >> > >> > > > > > starters, >> > >> > > > > > if the new methods were all reliant on one config, there is >> > >> > > likelihood >> > >> > > > > > that the >> > >> > > > > > shortcomings for this approach would be similar to what we >> > >> faced if >> > >> > > we >> > >> > > > > let >> > >> > > > > > request.timeout.ms control all method timeouts. In >> > comparison, >> > >> > > adding >> > >> > > > > > overloads >> > >> > > > > > does not have this problem. >> > >> > > > > > >> > >> > > > > > If you have further thoughts, please let me know. >> > >> > > > > > >> > >> > > > > > Richard >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > On Mon, Mar 19, 2018 at 5:12 PM, Ismael Juma < >> > ism...@juma.me.uk >> > >> > >> > >> > > > wrote: >> > >> > > > > > >> > >> > > > > >> Hi, >> > >> > > > > >> >> > >> > > > > >> An option that is not currently covered in the KIP is to >> > have a >> > >> > > > separate >> > >> > > > > >> config max.block.ms, which is similar to the producer >> config >> > >> with >> > >> > > the >> > >> > > > > >> same >> > >> > > > > >> name. This came up during the KAFKA-2391 discussion. I >> think >> > >> it's >> > >> > > > clear >> > >> > > > > >> that we can't rely on request.timeout.ms, so the >> decision is >> > >> > > between >> > >> > > > > >> adding >> > >> > > > > >> overloads or adding a new config. People seemed to be >> leaning >> > >> > > towards >> > >> > > > > the >> > >> > > > > >> latter in KAFKA-2391, but Jason makes a good point that >> the >> > >> > > overloads >> > >> > > > > are >> > >> > > > > >> more flexible. A couple of questions from me: >> > >> > > > > >> >> > >> > > > > >> 1. Do we need the additional flexibility? >> > >> > > > > >> 2. If we do, do we need it for every blocking method? >> > >> > > > > >> >> > >> > > > > >> Ismael >> > >> > > > > >> >> > >> > > > > >> On Mon, Mar 19, 2018 at 5:03 PM, Richard Yu < >> > >> > > > yohan.richard...@gmail.com >> > >> > > > > > >> > >> > > > > >> wrote: >> > >> > > > > >> >> > >> > > > > >> > Hi Guozhang, >> > >> > > > > >> > >> > >> > > > > >> > I made some clarifications to KIP-266, namely: >> > >> > > > > >> > 1. Stated more specifically that commitSync will accept >> > user >> > >> > > input. >> > >> > > > > >> > 2. fetchCommittedOffsets(): Made its role in blocking >> more >> > >> clear >> > >> > > to >> > >> > > > > the >> > >> > > > > >> > reader. >> > >> > > > > >> > 3. Sketched what would happen when time limit is >> exceeded. >> > >> > > > > >> > >> > >> > > > > >> > These changes should make the KIP easier to understand. >> > >> > > > > >> > >> > >> > > > > >> > Cheers, >> > >> > > > > >> > Richard >> > >> > > > > >> > >> > >> > > > > >> > On Mon, Mar 19, 2018 at 9:33 AM, Guozhang Wang < >> > >> > > wangg...@gmail.com> >> > >> > > > > >> wrote: >> > >> > > > > >> > >> > >> > > > > >> > > Hi Richard, >> > >> > > > > >> > > >> > >> > > > > >> > > I made a pass over the KIP again, some more >> > clarifications >> > >> / >> > >> > > > > comments: >> > >> > > > > >> > > >> > >> > > > > >> > > 1. seek() call itself is not blocking, only the >> following >> > >> > poll() >> > >> > > > > call >> > >> > > > > >> may >> > >> > > > > >> > > be blocking as the actually metadata rq will happen. >> > >> > > > > >> > > >> > >> > > > > >> > > 2. I saw you did not include Consumer.partitionFor(), >> > >> > > > > >> > > Consumer.OffsetAndTimestamp() and >> Consumer.listTopics() >> > in >> > >> > your >> > >> > > > KIP. >> > >> > > > > >> > After >> > >> > > > > >> > > a second thought, I think this may be a better idea to >> > not >> > >> > > tackle >> > >> > > > > >> them in >> > >> > > > > >> > > the same KIP, and probably we should consider whether >> we >> > >> would >> > >> > > > > change >> > >> > > > > >> the >> > >> > > > > >> > > behavior or not in another discussion. So I agree to >> not >> > >> > include >> > >> > > > > them. >> > >> > > > > >> > > >> > >> > > > > >> > > 3. In your wiki you mentioned "Another change shall be >> > >> made to >> > >> > > > > >> > > KafkaConsumer#poll(), due to its call to >> > >> > updateFetchPositions() >> > >> > > > > which >> > >> > > > > >> > > blocks indefinitely." This part may a bit obscure to >> most >> > >> > > readers >> > >> > > > > >> who's >> > >> > > > > >> > not >> > >> > > > > >> > > familiar with the KafkaConsumer internals, could you >> > please >> > >> > add >> > >> > > > more >> > >> > > > > >> > > elaborations. More specifically, I think the root >> causes >> > of >> > >> > the >> > >> > > > > public >> > >> > > > > >> > APIs >> > >> > > > > >> > > mentioned are a bit different while the KIP's >> explanation >> > >> > sounds >> > >> > > > > like >> > >> > > > > >> > they >> > >> > > > > >> > > are due to the same reason: >> > >> > > > > >> > > >> > >> > > > > >> > > 3.1 fetchCommittedOffsets(): this internal call will >> > block >> > >> > > forever >> > >> > > > > if >> > >> > > > > >> the >> > >> > > > > >> > > committed offsets cannot be fetched successfully and >> > affect >> > >> > > > > position() >> > >> > > > > >> > and >> > >> > > > > >> > > committed(). We need to break out of its internal >> while >> > >> loop. >> > >> > > > > >> > > 3.2 position() itself will while loop when offsets >> cannot >> > >> be >> > >> > > > > >> retrieved in >> > >> > > > > >> > > the underlying async call. We need to break out this >> > while >> > >> > loop. >> > >> > > > > >> > > 3.3 commitSync() passed Long.MAX_VALUE as the timeout >> > >> value, >> > >> > we >> > >> > > > > should >> > >> > > > > >> > take >> > >> > > > > >> > > the user specified timeouts when applicable. >> > >> > > > > >> > > >> > >> > > > > >> > > >> > >> > > > > >> > > >> > >> > > > > >> > > Guozhang >> > >> > > > > >> > > >> > >> > > > > >> > > On Sat, Mar 17, 2018 at 4:44 PM, Richard Yu < >> > >> > > > > >> yohan.richard...@gmail.com> >> > >> > > > > >> > > wrote: >> > >> > > > > >> > > >> > >> > > > > >> > > > Actually, what I said above is inaccurate. In >> > >> > > > > >> > > > testSeekAndCommitWithBrokerFailures, >> > >> > TestUtils.waitUntilTrue >> > >> > > > > >> blocks, >> > >> > > > > >> > not >> > >> > > > > >> > > > seek. >> > >> > > > > >> > > > My assumption is that seek did not update >> correctly. I >> > >> will >> > >> > be >> > >> > > > > >> digging >> > >> > > > > >> > > > further into this. >> > >> > > > > >> > > > >> > >> > > > > >> > > > >> > >> > > > > >> > > > >> > >> > > > > >> > > > On Sat, Mar 17, 2018 at 4:16 PM, Richard Yu < >> > >> > > > > >> > yohan.richard...@gmail.com> >> > >> > > > > >> > > > wrote: >> > >> > > > > >> > > > >> > >> > > > > >> > > > > One more thing: when looking through tests, I have >> > >> > realized >> > >> > > > that >> > >> > > > > >> > seek() >> > >> > > > > >> > > > > methods can potentially block indefinitely. As you >> > well >> > >> > > know, >> > >> > > > > >> seek() >> > >> > > > > >> > is >> > >> > > > > >> > > > > called when pollOnce() or position() is active. >> Thus, >> > >> if >> > >> > > > > >> position() >> > >> > > > > >> > > > blocks >> > >> > > > > >> > > > > indefinitely, then so would seek(). Should >> bounding >> > >> seek() >> > >> > > > also >> > >> > > > > be >> > >> > > > > >> > > > included >> > >> > > > > >> > > > > in this KIP? >> > >> > > > > >> > > > > >> > >> > > > > >> > > > > Thanks, Richard >> > >> > > > > >> > > > > >> > >> > > > > >> > > > > On Sat, Mar 17, 2018 at 1:16 PM, Richard Yu < >> > >> > > > > >> > > yohan.richard...@gmail.com> >> > >> > > > > >> > > > > wrote: >> > >> > > > > >> > > > > >> > >> > > > > >> > > > >> Thanks for the advice, Jason >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> I have modified KIP-266 to include the java doc >> for >> > >> > > > committed() >> > >> > > > > >> and >> > >> > > > > >> > > > other >> > >> > > > > >> > > > >> blocking methods, and I also >> > >> > > > > >> > > > >> mentioned poll() which will also be bounded. Let >> me >> > >> know >> > >> > if >> > >> > > > > >> there is >> > >> > > > > >> > > > >> anything else. :) >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> Sincerely, Richard >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> On Sat, Mar 17, 2018 at 12:00 PM, Jason >> Gustafson < >> > >> > > > > >> > ja...@confluent.io >> > >> > > > > >> > > > >> > >> > > > > >> > > > >> wrote: >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >>> Hi Richard, >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> Thanks for the updates. I'm really glad you >> picked >> > >> this >> > >> > > up. >> > >> > > > A >> > >> > > > > >> > couple >> > >> > > > > >> > > > >>> minor >> > >> > > > > >> > > > >>> comments: >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> 1. Can you list the full set of new APIs >> explicitly >> > >> in >> > >> > the >> > >> > > > > KIP? >> > >> > > > > >> > > > >>> Currently I >> > >> > > > > >> > > > >>> only see the javadoc for `position()`. >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> 2. We should consider adding `TimeUnit` to the >> new >> > >> > methods >> > >> > > > to >> > >> > > > > >> avoid >> > >> > > > > >> > > > unit >> > >> > > > > >> > > > >>> confusion. I know it's inconsistent with the >> poll() >> > >> API, >> > >> > > > but I >> > >> > > > > >> > think >> > >> > > > > >> > > it >> > >> > > > > >> > > > >>> was >> > >> > > > > >> > > > >>> probably a mistake not to include it there, so >> > better >> > >> > not >> > >> > > to >> > >> > > > > >> double >> > >> > > > > >> > > > down >> > >> > > > > >> > > > >>> on >> > >> > > > > >> > > > >>> that mistake. And note that we do already have >> > >> > > `close(long, >> > >> > > > > >> > > TimeUnit)`. >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> Other than that, I think the current KIP seems >> > >> > reasonable. >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> Thanks, >> > >> > > > > >> > > > >>> Jason >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> On Wed, Mar 14, 2018 at 5:00 PM, Richard Yu < >> > >> > > > > >> > > > yohan.richard...@gmail.com> >> > >> > > > > >> > > > >>> wrote: >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >>> > Note to all: I have included bounding >> > commitSync() >> > >> and >> > >> > > > > >> > committed() >> > >> > > > > >> > > in >> > >> > > > > >> > > > >>> this >> > >> > > > > >> > > > >>> > KIP. >> > >> > > > > >> > > > >>> > >> > >> > > > > >> > > > >>> > On Sun, Mar 11, 2018 at 5:05 PM, Richard Yu < >> > >> > > > > >> > > > >>> yohan.richard...@gmail.com> >> > >> > > > > >> > > > >>> > wrote: >> > >> > > > > >> > > > >>> > >> > >> > > > > >> > > > >>> > > Hi all, >> > >> > > > > >> > > > >>> > > >> > >> > > > > >> > > > >>> > > I updated the KIP where overloading >> position() >> > is >> > >> > now >> > >> > > > the >> > >> > > > > >> > favored >> > >> > > > > >> > > > >>> > approach. >> > >> > > > > >> > > > >>> > > Bounding position() using requestTimeoutMs >> has >> > >> been >> > >> > > > listed >> > >> > > > > >> as >> > >> > > > > >> > > > >>> rejected. >> > >> > > > > >> > > > >>> > > >> > >> > > > > >> > > > >>> > > Any thoughts? >> > >> > > > > >> > > > >>> > > >> > >> > > > > >> > > > >>> > > On Tue, Mar 6, 2018 at 6:00 PM, Guozhang >> Wang < >> > >> > > > > >> > > wangg...@gmail.com> >> > >> > > > > >> > > > >>> > wrote: >> > >> > > > > >> > > > >>> > > >> > >> > > > > >> > > > >>> > >> I agree that adding the overloads is most >> > >> flexible. >> > >> > > But >> > >> > > > > >> going >> > >> > > > > >> > > for >> > >> > > > > >> > > > >>> that >> > >> > > > > >> > > > >>> > >> direction we'd do that for all the blocking >> > call >> > >> > that >> > >> > > > > I've >> > >> > > > > >> > > listed >> > >> > > > > >> > > > >>> above, >> > >> > > > > >> > > > >>> > >> with this timeout value covering the >> > end-to-end >> > >> > > waiting >> > >> > > > > >> time. >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> Guozhang >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> On Tue, Mar 6, 2018 at 10:02 AM, Ted Yu < >> > >> > > > > >> yuzhih...@gmail.com> >> > >> > > > > >> > > > >>> wrote: >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> > bq. The most flexible option is to add >> > >> overloads >> > >> > to >> > >> > > > the >> > >> > > > > >> > > consumer >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> > This option is flexible. >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> > Looking at the tail of SPARK-18057, Spark >> > dev >> > >> > > voiced >> > >> > > > > the >> > >> > > > > >> > same >> > >> > > > > >> > > > >>> choice. >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> > +1 for adding overload with timeout >> > parameter. >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> > Cheers >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> > On Mon, Mar 5, 2018 at 2:42 PM, Jason >> > >> Gustafson < >> > >> > > > > >> > > > >>> ja...@confluent.io> >> > >> > > > > >> > > > >>> > >> > wrote: >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> > > @Guozhang I probably have suggested all >> > >> options >> > >> > > at >> > >> > > > > some >> > >> > > > > >> > > point >> > >> > > > > >> > > > or >> > >> > > > > >> > > > >>> > >> another, >> > >> > > > > >> > > > >>> > >> > > including most recently, the current >> KIP! >> > I >> > >> was >> > >> > > > > >> thinking >> > >> > > > > >> > > that >> > >> > > > > >> > > > >>> > >> practically >> > >> > > > > >> > > > >>> > >> > > speaking, the request timeout defines >> how >> > >> long >> > >> > > the >> > >> > > > > >> user is >> > >> > > > > >> > > > >>> willing >> > >> > > > > >> > > > >>> > to >> > >> > > > > >> > > > >>> > >> > wait >> > >> > > > > >> > > > >>> > >> > > for a response. The consumer doesn't >> > really >> > >> > have >> > >> > > a >> > >> > > > > >> complex >> > >> > > > > >> > > > send >> > >> > > > > >> > > > >>> > >> process >> > >> > > > > >> > > > >>> > >> > > like the producer for any of these >> APIs, >> > so >> > >> I >> > >> > > > wasn't >> > >> > > > > >> sure >> > >> > > > > >> > > how >> > >> > > > > >> > > > >>> much >> > >> > > > > >> > > > >>> > >> > benefit >> > >> > > > > >> > > > >>> > >> > > there would be from having more >> granular >> > >> > control >> > >> > > > over >> > >> > > > > >> > > timeouts >> > >> > > > > >> > > > >>> (in >> > >> > > > > >> > > > >>> > the >> > >> > > > > >> > > > >>> > >> > end, >> > >> > > > > >> > > > >>> > >> > > KIP-91 just adds a single timeout to >> > control >> > >> > the >> > >> > > > > whole >> > >> > > > > >> > > send). >> > >> > > > > >> > > > >>> That >> > >> > > > > >> > > > >>> > >> said, >> > >> > > > > >> > > > >>> > >> > it >> > >> > > > > >> > > > >>> > >> > > might indeed be better to avoid >> > overloading >> > >> the >> > >> > > > > config >> > >> > > > > >> as >> > >> > > > > >> > > you >> > >> > > > > >> > > > >>> > suggest >> > >> > > > > >> > > > >>> > >> > since >> > >> > > > > >> > > > >>> > >> > > at least it avoids inconsistency with >> the >> > >> > > > producer's >> > >> > > > > >> > usage. >> > >> > > > > >> > > > >>> > >> > > >> > >> > > > > >> > > > >>> > >> > > The most flexible option is to add >> > >> overloads to >> > >> > > the >> > >> > > > > >> > consumer >> > >> > > > > >> > > > so >> > >> > > > > >> > > > >>> that >> > >> > > > > >> > > > >>> > >> > users >> > >> > > > > >> > > > >>> > >> > > can pass the timeout directly. I'm not >> > sure >> > >> if >> > >> > > that >> > >> > > > > is >> > >> > > > > >> > more >> > >> > > > > >> > > or >> > >> > > > > >> > > > >>> less >> > >> > > > > >> > > > >>> > >> > > annoying than a new config, but I've >> found >> > >> > config >> > >> > > > > >> > timeouts a >> > >> > > > > >> > > > >>> little >> > >> > > > > >> > > > >>> > >> > > constraining in practice. For example, >> I >> > >> could >> > >> > > > > imagine >> > >> > > > > >> > users >> > >> > > > > >> > > > >>> wanting >> > >> > > > > >> > > > >>> > >> to >> > >> > > > > >> > > > >>> > >> > > wait longer for an offset commit >> operation >> > >> > than a >> > >> > > > > >> position >> > >> > > > > >> > > > >>> lookup; >> > >> > > > > >> > > > >>> > if >> > >> > > > > >> > > > >>> > >> the >> > >> > > > > >> > > > >>> > >> > > latter isn't timely, users can just >> pause >> > >> the >> > >> > > > > partition >> > >> > > > > >> > and >> > >> > > > > >> > > > >>> continue >> > >> > > > > >> > > > >>> > >> > > fetching on others. If you cannot >> commit >> > >> > offsets, >> > >> > > > > >> however, >> > >> > > > > >> > > it >> > >> > > > > >> > > > >>> might >> > >> > > > > >> > > > >>> > be >> > >> > > > > >> > > > >>> > >> > > safer for an application to wait >> > >> availability >> > >> > of >> > >> > > > the >> > >> > > > > >> > > > coordinator >> > >> > > > > >> > > > >>> > than >> > >> > > > > >> > > > >>> > >> > > continuing. >> > >> > > > > >> > > > >>> > >> > > >> > >> > > > > >> > > > >>> > >> > > -Jason >> > >> > > > > >> > > > >>> > >> > > >> > >> > > > > >> > > > >>> > >> > > On Sun, Mar 4, 2018 at 10:14 PM, >> Guozhang >> > >> Wang >> > >> > < >> > >> > > > > >> > > > >>> wangg...@gmail.com> >> > >> > > > > >> > > > >>> > >> > wrote: >> > >> > > > > >> > > > >>> > >> > > >> > >> > > > > >> > > > >>> > >> > > > Hello Richard, >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > Thanks for the proposed KIP. I have a >> > >> couple >> > >> > of >> > >> > > > > >> general >> > >> > > > > >> > > > >>> comments: >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > 1. I'm not sure if piggy-backing the >> > >> timeout >> > >> > > > > >> exception >> > >> > > > > >> > on >> > >> > > > > >> > > > the >> > >> > > > > >> > > > >>> > >> > > > existing requestTimeoutMs configured >> in >> > " >> > >> > > > > >> > > request.timeout.ms >> > >> > > > > >> > > > " >> > >> > > > > >> > > > >>> is a >> > >> > > > > >> > > > >>> > >> good >> > >> > > > > >> > > > >>> > >> > > > idea >> > >> > > > > >> > > > >>> > >> > > > since a) it is a general config that >> > >> applies >> > >> > > for >> > >> > > > > all >> > >> > > > > >> > types >> > >> > > > > >> > > > of >> > >> > > > > >> > > > >>> > >> requests, >> > >> > > > > >> > > > >>> > >> > > and >> > >> > > > > >> > > > >>> > >> > > > 2) using it to cover all the phases >> of >> > an >> > >> API >> > >> > > > call, >> > >> > > > > >> > > > including >> > >> > > > > >> > > > >>> > >> network >> > >> > > > > >> > > > >>> > >> > > round >> > >> > > > > >> > > > >>> > >> > > > trip and potential metadata refresh >> is >> > >> shown >> > >> > to >> > >> > > > not >> > >> > > > > >> be a >> > >> > > > > >> > > > good >> > >> > > > > >> > > > >>> > idea, >> > >> > > > > >> > > > >>> > >> as >> > >> > > > > >> > > > >>> > >> > > > illustrated in KIP-91: >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > https://cwiki.apache.org/confl >> > >> > > > > >> uence/display/KAFKA/KIP- >> > >> > > > > >> > > > >>> > >> > > > 91+Provide+Intuitive+User+ >> > >> > > > Timeouts+in+The+Producer >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > In fact, I think in KAFKA-4879 which >> is >> > >> aimed >> > >> > > for >> > >> > > > > the >> > >> > > > > >> > same >> > >> > > > > >> > > > >>> issue >> > >> > > > > >> > > > >>> > as >> > >> > > > > >> > > > >>> > >> > > > KAFKA-6608, >> > >> > > > > >> > > > >>> > >> > > > Jason has suggested we use a new >> config >> > >> for >> > >> > the >> > >> > > > > API. >> > >> > > > > >> > Maybe >> > >> > > > > >> > > > >>> this >> > >> > > > > >> > > > >>> > >> would >> > >> > > > > >> > > > >>> > >> > be >> > >> > > > > >> > > > >>> > >> > > a >> > >> > > > > >> > > > >>> > >> > > > more intuitive manner than reusing >> the >> > >> > > > > >> > request.timeout.ms >> > >> > > > > >> > > > >>> config. >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > 2. Besides the Consumer.position() >> call, >> > >> > there >> > >> > > > are >> > >> > > > > a >> > >> > > > > >> > > couple >> > >> > > > > >> > > > of >> > >> > > > > >> > > > >>> > more >> > >> > > > > >> > > > >>> > >> > > > blocking calls today that could >> result >> > in >> > >> > > > infinite >> > >> > > > > >> > > blocking: >> > >> > > > > >> > > > >>> > >> > > > Consumer.commitSync() and >> > >> > Consumer.committed(), >> > >> > > > > >> should >> > >> > > > > >> > > they >> > >> > > > > >> > > > be >> > >> > > > > >> > > > >>> > >> > considered >> > >> > > > > >> > > > >>> > >> > > > in this KIP as well? >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > 3. There are a few other APIs that >> are >> > >> today >> > >> > > > > relying >> > >> > > > > >> on >> > >> > > > > >> > > > >>> > >> > > request.timeout.ms >> > >> > > > > >> > > > >>> > >> > > > already for breaking the infinite >> > >> blocking, >> > >> > > > namely >> > >> > > > > >> > > > >>> > >> > > Consumer.partitionFor(), >> > >> > > > > >> > > > >>> > >> > > > Consumer.OffsetAndTimestamp() and >> > >> > > > > >> Consumer.listTopics(), >> > >> > > > > >> > > if >> > >> > > > > >> > > > >>> we are >> > >> > > > > >> > > > >>> > >> > making >> > >> > > > > >> > > > >>> > >> > > > the other blocking calls to be >> relying a >> > >> new >> > >> > > > config >> > >> > > > > >> as >> > >> > > > > >> > > > >>> suggested >> > >> > > > > >> > > > >>> > in >> > >> > > > > >> > > > >>> > >> 1) >> > >> > > > > >> > > > >>> > >> > > > above, should we also change the >> > >> semantics of >> > >> > > > these >> > >> > > > > >> API >> > >> > > > > >> > > > >>> functions >> > >> > > > > >> > > > >>> > >> for >> > >> > > > > >> > > > >>> > >> > > > consistency? >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > Guozhang >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > On Sun, Mar 4, 2018 at 11:13 AM, >> Richard >> > >> Yu < >> > >> > > > > >> > > > >>> > >> > yohan.richard...@gmail.com> >> > >> > > > > >> > > > >>> > >> > > > wrote: >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > > Hi all, >> > >> > > > > >> > > > >>> > >> > > > > >> > >> > > > > >> > > > >>> > >> > > > > I would like to discuss a potential >> > >> change >> > >> > > > which >> > >> > > > > >> would >> > >> > > > > >> > > be >> > >> > > > > >> > > > >>> made >> > >> > > > > >> > > > >>> > to >> > >> > > > > >> > > > >>> > >> > > > > KafkaConsumer: >> > >> > > > > >> > > > >>> > >> > > > > https://cwiki.apache.org/ >> > >> > > > > confluence/pages/viewpage >> > >> > > > > >> . >> > >> > > > > >> > > > >>> > >> > > > action?pageId=75974886 >> > >> > > > > >> > > > >>> > >> > > > > >> > >> > > > > >> > > > >>> > >> > > > > Thanks, >> > >> > > > > >> > > > >>> > >> > > > > Richard Yu >> > >> > > > > >> > > > >>> > >> > > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > > -- >> > >> > > > > >> > > > >>> > >> > > > -- Guozhang >> > >> > > > > >> > > > >>> > >> > > > >> > >> > > > > >> > > > >>> > >> > > >> > >> > > > > >> > > > >>> > >> > >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > >> -- >> > >> > > > > >> > > > >>> > >> -- Guozhang >> > >> > > > > >> > > > >>> > >> >> > >> > > > > >> > > > >>> > > >> > >> > > > > >> > > > >>> > > >> > >> > > > > >> > > > >>> > >> > >> > > > > >> > > > >>> >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > >> >> > >> > > > > >> > > > > >> > >> > > > > >> > > > >> > >> > > > > >> > > >> > >> > > > > >> > > >> > >> > > > > >> > > >> > >> > > > > >> > > -- >> > >> > > > > >> > > -- Guozhang >> > >> > > > > >> > > >> > >> > > > > >> > >> > >> > > > > >> >> > >> > > > > > >> > >> > > > > > >> > >> > > > > >> > >> > > > >> > >> > > >> > >> > >> > >> > >> > >> > >> > >> > -- >> > >> > -- Guozhang >> > >> > >> > >> >> > > >> > > >> > >> >> >> >> -- >> -- Guozhang >> > >
