Hey Becket, Thanks for the KIP! The approach seems reasonable. One clarification: is the intent to do the splitting after the broker rejects the request with MESSAGE_TOO_LARGE, or prior to sending if the configured batch size is exceeded?
-Jason On Mon, Mar 13, 2017 at 8:10 PM, Becket Qin <becket....@gmail.com> wrote: > Bump up the thread for further comments. If there is no more comments on > the KIP I will start the voting thread on Wed. > > Thanks, > > Jiangjie (Becket) Qin > > On Tue, Mar 7, 2017 at 9:48 AM, Becket Qin <becket....@gmail.com> wrote: > > > Hi Dong, > > > > Thanks for the comments. > > > > The patch is mostly for proof of concept in case there is any concern > > about the implementation which is indeed a little tricky. > > > > The new metric has already been mentioned in the Public Interface Change > > section. > > > > I added the reasoning about how the compression ratio > > improving/deteriorate steps are determined in the wiki. > > > > Thanks, > > > > Jiangjie (Becket) Qin > > > > > > On Mon, Mar 6, 2017 at 4:42 PM, Dong Lin <lindon...@gmail.com> wrote: > > > >> Hey Becket, > >> > >> I am wondering if we should first vote for the KIP before reviewing the > >> patch. I have two comments below: > >> > >> - Should we specify the new sensors as part of interface change in the > >> KIP? > >> - The KIP proposes to increase estimated compression ratio by 0.05 for > >> each > >> underestimation and decrement the estimation by 0.005 for each > >> overestimation. Why are these two values chosen? I think there is some > >> tradeoff in selecting the value. Can the KIP be more explicit about the > >> tradeoff and explain how these two values would impact producer's > >> performance? > >> > >> Thanks, > >> Dong > >> > >> > >> On Sat, Mar 4, 2017 at 11:42 AM, Becket Qin <becket....@gmail.com> > wrote: > >> > >> > I have updated the KIP based on the latest discussion. Please check > and > >> let > >> > me know if there is any further concern. > >> > > >> > Thanks, > >> > > >> > Jiangjie (Becket) Qin > >> > > >> > On Sat, Mar 4, 2017 at 10:56 AM, Becket Qin <becket....@gmail.com> > >> wrote: > >> > > >> > > Actually second thought on this, rate might be better for two > reasons: > >> > > 1. Most of the metrics in the producer we already have are using > rate > >> > > instead of count. > >> > > 2. If a service is bounced, the count will be reset to 0, but it > does > >> not > >> > > affect rate. > >> > > > >> > > I'll make the change. > >> > > > >> > > Thanks, > >> > > > >> > > Jiangjie (Becket) Qin > >> > > > >> > > On Sat, Mar 4, 2017 at 10:27 AM, Becket Qin <becket....@gmail.com> > >> > wrote: > >> > > > >> > >> Hi Dong, > >> > >> > >> > >> Yes, there is a sensor in the patch about the split occurrence. > >> > >> > >> > >> Currently it is a count instead of rate. In practice, it seems > count > >> is > >> > >> easier to use in this case. But I am open to change. > >> > >> > >> > >> Thanks, > >> > >> > >> > >> Jiangjie (Becket) Qin > >> > >> > >> > >> On Fri, Mar 3, 2017 at 7:43 PM, Dong Lin <lindon...@gmail.com> > >> wrote: > >> > >> > >> > >>> Hey Becket, > >> > >>> > >> > >>> I haven't looked at the patch yet. But since we are going to try > the > >> > >>> split-on-oversize solution, should the KIP also add a sensor that > >> shows > >> > >>> the > >> > >>> rate of split per second and the probability of split? > >> > >>> > >> > >>> Thanks, > >> > >>> Dong > >> > >>> > >> > >>> > >> > >>> On Fri, Mar 3, 2017 at 6:39 PM, Becket Qin <becket....@gmail.com> > >> > wrote: > >> > >>> > >> > >>> > Just to clarify, the implementation is basically what I > mentioned > >> > above > >> > >>> > (split/resend + adjusted estimation evolving algorithm) and > >> changing > >> > >>> the > >> > >>> > compression ratio estimation to be per topic. > >> > >>> > > >> > >>> > Thanks, > >> > >>> > > >> > >>> > Jiangjie (Becket) Qin > >> > >>> > > >> > >>> > On Fri, Mar 3, 2017 at 6:36 PM, Becket Qin < > becket....@gmail.com> > >> > >>> wrote: > >> > >>> > > >> > >>> > > I went ahead and have a patch submitted here: > >> > >>> > > https://github.com/apache/kafka/pull/2638 > >> > >>> > > > >> > >>> > > Per Joel's suggestion, I changed the compression ratio to be > per > >> > >>> topic as > >> > >>> > > well. It seems working well. Since there is an important > >> behavior > >> > >>> change > >> > >>> > > and a new sensor is added, I'll keep the KIP and update it > >> > according. > >> > >>> > > > >> > >>> > > Thanks, > >> > >>> > > > >> > >>> > > Jiangjie (Becket) Qin > >> > >>> > > > >> > >>> > > On Mon, Feb 27, 2017 at 3:50 PM, Joel Koshy < > >> jjkosh...@gmail.com> > >> > >>> wrote: > >> > >>> > > > >> > >>> > >> > > >> > >>> > >> > Lets say we sent the batch over the wire and received a > >> > >>> > >> > RecordTooLargeException, how do we split it as once we add > >> the > >> > >>> message > >> > >>> > >> to > >> > >>> > >> > the batch we loose the message level granularity. We will > >> have > >> > to > >> > >>> > >> > decompress, do deep iteration and split and again compress. > >> > right? > >> > >>> > This > >> > >>> > >> > looks like a performance bottle neck in case of multi topic > >> > >>> producers > >> > >>> > >> like > >> > >>> > >> > mirror maker. > >> > >>> > >> > > >> > >>> > >> > >> > >>> > >> Yes, but these should be outliers if we do estimation on a > >> > per-topic > >> > >>> > basis > >> > >>> > >> and if we target a conservative-enough compression ratio. The > >> > >>> producer > >> > >>> > >> should also avoid sending over the wire if it can be made > >> aware of > >> > >>> the > >> > >>> > >> max-message size limit on the broker, and split if it > >> determines > >> > >>> that a > >> > >>> > >> record exceeds the broker's config. Ideally this should be > >> part of > >> > >>> topic > >> > >>> > >> metadata but is not - so it could be off a periodic > >> > describe-configs > >> > >>> > >> <https://cwiki.apache.org/confluence/display/KAFKA/KIP-4+-+ > >> > >>> > >> Command+line+and+centralized+administrative+operations#KIP- > >> > >>> > >> 4-Commandlineandcentralizedadministrativeoperations-Describe > >> > >>> > >> ConfigsRequest> > >> > >>> > >> (which isn't available yet). This doesn't remove the need to > >> split > >> > >>> and > >> > >>> > >> recompress though. > >> > >>> > >> > >> > >>> > >> > >> > >>> > >> > On Mon, Feb 27, 2017 at 10:51 AM, Becket Qin < > >> > >>> becket....@gmail.com> > >> > >>> > >> wrote: > >> > >>> > >> > > >> > >>> > >> > > Hey Mayuresh, > >> > >>> > >> > > > >> > >>> > >> > > 1) The batch would be split when an > >> RecordTooLargeException is > >> > >>> > >> received. > >> > >>> > >> > > 2) Not lower the actual compression ratio, but lower the > >> > >>> estimated > >> > >>> > >> > > compression ratio "according to" the Actual Compression > >> > >>> Ratio(ACR). > >> > >>> > >> > > > >> > >>> > >> > > An example, let's start with Estimated Compression Ratio > >> > (ECR) = > >> > >>> > 1.0. > >> > >>> > >> Say > >> > >>> > >> > > the compression ratio of ACR is ~0.8, instead of letting > >> the > >> > ECR > >> > >>> > >> dropped > >> > >>> > >> > to > >> > >>> > >> > > 0.8 very quickly, we only drop 0.001 every time when ACR > < > >> > ECR. > >> > >>> > >> However, > >> > >>> > >> > > once we see an ACR > ECR, we increment ECR by 0.05. If a > >> > >>> > >> > > RecordTooLargeException is received, we reset the ECR > back > >> to > >> > >>> 1.0 > >> > >>> > and > >> > >>> > >> > split > >> > >>> > >> > > the batch. > >> > >>> > >> > > > >> > >>> > >> > > Thanks, > >> > >>> > >> > > > >> > >>> > >> > > Jiangjie (Becket) Qin > >> > >>> > >> > > > >> > >>> > >> > > > >> > >>> > >> > > > >> > >>> > >> > > On Mon, Feb 27, 2017 at 10:30 AM, Mayuresh Gharat < > >> > >>> > >> > > gharatmayures...@gmail.com> wrote: > >> > >>> > >> > > > >> > >>> > >> > > > Hi Becket, > >> > >>> > >> > > > > >> > >>> > >> > > > Seems like an interesting idea. > >> > >>> > >> > > > I had couple of questions : > >> > >>> > >> > > > 1) How do we decide when the batch should be split? > >> > >>> > >> > > > 2) What do you mean by slowly lowering the "actual" > >> > >>> compression > >> > >>> > >> ratio? > >> > >>> > >> > > > An example would really help here. > >> > >>> > >> > > > > >> > >>> > >> > > > Thanks, > >> > >>> > >> > > > > >> > >>> > >> > > > Mayuresh > >> > >>> > >> > > > > >> > >>> > >> > > > On Fri, Feb 24, 2017 at 3:17 PM, Becket Qin < > >> > >>> becket....@gmail.com > >> > >>> > > > >> > >>> > >> > > wrote: > >> > >>> > >> > > > > >> > >>> > >> > > > > Hi Jay, > >> > >>> > >> > > > > > >> > >>> > >> > > > > Yeah, I got your point. > >> > >>> > >> > > > > > >> > >>> > >> > > > > I think there might be a solution which do not > require > >> > >>> adding a > >> > >>> > >> new > >> > >>> > >> > > > > configuration. We can start from a very conservative > >> > >>> compression > >> > >>> > >> > ratio > >> > >>> > >> > > > say > >> > >>> > >> > > > > 1.0 and lower it very slowly according to the actual > >> > >>> compression > >> > >>> > >> > ratio > >> > >>> > >> > > > > until we hit a point that we have to split a batch. > At > >> > that > >> > >>> > >> point, we > >> > >>> > >> > > > > exponentially back off on the compression ratio. The > >> idea > >> > is > >> > >>> > >> somewhat > >> > >>> > >> > > > like > >> > >>> > >> > > > > TCP. This should help avoid frequent split. > >> > >>> > >> > > > > > >> > >>> > >> > > > > The upper bound of the batch size is also a little > >> awkward > >> > >>> today > >> > >>> > >> > > because > >> > >>> > >> > > > we > >> > >>> > >> > > > > say the batch size is based on compressed size, but > >> users > >> > >>> cannot > >> > >>> > >> set > >> > >>> > >> > it > >> > >>> > >> > > > to > >> > >>> > >> > > > > the max message size because that will result in > >> oversized > >> > >>> > >> messages. > >> > >>> > >> > > With > >> > >>> > >> > > > > this change we will be able to allow the users to set > >> the > >> > >>> > message > >> > >>> > >> > size > >> > >>> > >> > > to > >> > >>> > >> > > > > close to max message size. > >> > >>> > >> > > > > > >> > >>> > >> > > > > However the downside is that there could be latency > >> spikes > >> > >>> in > >> > >>> > the > >> > >>> > >> > > system > >> > >>> > >> > > > in > >> > >>> > >> > > > > this case due to the splitting, especially when there > >> are > >> > >>> many > >> > >>> > >> > messages > >> > >>> > >> > > > > need to be split at the same time. That could > >> potentially > >> > >>> be an > >> > >>> > >> issue > >> > >>> > >> > > for > >> > >>> > >> > > > > some users. > >> > >>> > >> > > > > > >> > >>> > >> > > > > What do you think about this approach? > >> > >>> > >> > > > > > >> > >>> > >> > > > > Thanks, > >> > >>> > >> > > > > > >> > >>> > >> > > > > Jiangjie (Becket) Qin > >> > >>> > >> > > > > > >> > >>> > >> > > > > > >> > >>> > >> > > > > > >> > >>> > >> > > > > On Thu, Feb 23, 2017 at 1:31 PM, Jay Kreps < > >> > >>> j...@confluent.io> > >> > >>> > >> wrote: > >> > >>> > >> > > > > > >> > >>> > >> > > > > > Hey Becket, > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > Yeah that makes sense. > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > I agree that you'd really have to both fix the > >> > estimation > >> > >>> > (i.e. > >> > >>> > >> > make > >> > >>> > >> > > it > >> > >>> > >> > > > > per > >> > >>> > >> > > > > > topic or make it better estimate the high > >> percentiles) > >> > AND > >> > >>> > have > >> > >>> > >> the > >> > >>> > >> > > > > > recovery mechanism. If you are underestimating > often > >> and > >> > >>> then > >> > >>> > >> > paying > >> > >>> > >> > > a > >> > >>> > >> > > > > high > >> > >>> > >> > > > > > recovery price that won't fly. > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > I think you take my main point though, which is > just > >> > that > >> > >>> I > >> > >>> > >> hate to > >> > >>> > >> > > > > exposes > >> > >>> > >> > > > > > these super low level options to users because it > is > >> so > >> > >>> hard > >> > >>> > to > >> > >>> > >> > > explain > >> > >>> > >> > > > > to > >> > >>> > >> > > > > > people what it means and how they should set it. So > >> if > >> > it > >> > >>> is > >> > >>> > >> > possible > >> > >>> > >> > > > to > >> > >>> > >> > > > > > make either some combination of better estimation > and > >> > >>> > splitting > >> > >>> > >> or > >> > >>> > >> > > > better > >> > >>> > >> > > > > > tolerance of overage that would be preferrable. > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > -Jay > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > On Thu, Feb 23, 2017 at 11:51 AM, Becket Qin < > >> > >>> > >> becket....@gmail.com > >> > >>> > >> > > > >> > >>> > >> > > > > wrote: > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > > @Dong, > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > Thanks for the comments. The default behavior of > >> the > >> > >>> > producer > >> > >>> > >> > won't > >> > >>> > >> > > > > > change. > >> > >>> > >> > > > > > > If the users want to use the uncompressed message > >> > size, > >> > >>> they > >> > >>> > >> > > probably > >> > >>> > >> > > > > > will > >> > >>> > >> > > > > > > also bump up the batch size to somewhere close to > >> the > >> > >>> max > >> > >>> > >> message > >> > >>> > >> > > > size. > >> > >>> > >> > > > > > > This would be in the document. BTW the default > >> batch > >> > >>> size is > >> > >>> > >> 16K > >> > >>> > >> > > > which > >> > >>> > >> > > > > is > >> > >>> > >> > > > > > > pretty small. > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > @Jay, > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > Yeah, we actually had debated quite a bit > >> internally > >> > >>> what is > >> > >>> > >> the > >> > >>> > >> > > best > >> > >>> > >> > > > > > > solution to this. > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > I completely agree it is a bug. In practice we > >> usually > >> > >>> leave > >> > >>> > >> some > >> > >>> > >> > > > > > headroom > >> > >>> > >> > > > > > > to allow the compressed size to grow a little if > >> the > >> > the > >> > >>> > >> original > >> > >>> > >> > > > > > messages > >> > >>> > >> > > > > > > are not compressible, for example, 1000 KB > instead > >> of > >> > >>> > exactly > >> > >>> > >> 1 > >> > >>> > >> > MB. > >> > >>> > >> > > > It > >> > >>> > >> > > > > is > >> > >>> > >> > > > > > > likely safe enough. > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > The major concern for the rejected alternative is > >> > >>> > >> performance. It > >> > >>> > >> > > > > largely > >> > >>> > >> > > > > > > depends on how frequent we need to split a batch, > >> i.e. > >> > >>> how > >> > >>> > >> likely > >> > >>> > >> > > the > >> > >>> > >> > > > > > > estimation can go off. If we only need to the > split > >> > work > >> > >>> > >> > > > occasionally, > >> > >>> > >> > > > > > the > >> > >>> > >> > > > > > > cost would be amortized so we don't need to worry > >> > about > >> > >>> it > >> > >>> > too > >> > >>> > >> > > much. > >> > >>> > >> > > > > > > However, it looks that for a producer with shared > >> > >>> topics, > >> > >>> > the > >> > >>> > >> > > > > estimation > >> > >>> > >> > > > > > is > >> > >>> > >> > > > > > > always off. As an example, consider two topics, > one > >> > with > >> > >>> > >> > > compression > >> > >>> > >> > > > > > ratio > >> > >>> > >> > > > > > > 0.6 the other 0.2, assuming exactly same traffic, > >> the > >> > >>> > average > >> > >>> > >> > > > > compression > >> > >>> > >> > > > > > > ratio would be roughly 0.4, which is not right > for > >> > >>> either of > >> > >>> > >> the > >> > >>> > >> > > > > topics. > >> > >>> > >> > > > > > So > >> > >>> > >> > > > > > > almost half of the batches (of the topics with > 0.6 > >> > >>> > compression > >> > >>> > >> > > ratio) > >> > >>> > >> > > > > > will > >> > >>> > >> > > > > > > end up larger than the configured batch size. > When > >> it > >> > >>> comes > >> > >>> > to > >> > >>> > >> > more > >> > >>> > >> > > > > > topics > >> > >>> > >> > > > > > > such as mirror maker, this becomes more > >> unpredictable. > >> > >>> To > >> > >>> > >> avoid > >> > >>> > >> > > > > frequent > >> > >>> > >> > > > > > > rejection / split of the batches, we need to > >> > configured > >> > >>> the > >> > >>> > >> batch > >> > >>> > >> > > > size > >> > >>> > >> > > > > > > pretty conservatively. This could actually hurt > the > >> > >>> > >> performance > >> > >>> > >> > > > because > >> > >>> > >> > > > > > we > >> > >>> > >> > > > > > > are shoehorn the messages that are highly > >> compressible > >> > >>> to a > >> > >>> > >> small > >> > >>> > >> > > > batch > >> > >>> > >> > > > > > so > >> > >>> > >> > > > > > > that the other topics that are not that > >> compressible > >> > >>> will > >> > >>> > not > >> > >>> > >> > > become > >> > >>> > >> > > > > too > >> > >>> > >> > > > > > > large with the same batch size. At LinkedIn, our > >> batch > >> > >>> size > >> > >>> > is > >> > >>> > >> > > > > configured > >> > >>> > >> > > > > > > to 64 KB because of this. I think we may actually > >> have > >> > >>> > better > >> > >>> > >> > > > batching > >> > >>> > >> > > > > if > >> > >>> > >> > > > > > > we just use the uncompressed message size and 800 > >> KB > >> > >>> batch > >> > >>> > >> size. > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > We did not think about loosening the message size > >> > >>> > restriction, > >> > >>> > >> > but > >> > >>> > >> > > > that > >> > >>> > >> > > > > > > sounds a viable solution given that the consumer > >> now > >> > can > >> > >>> > fetch > >> > >>> > >> > > > > oversized > >> > >>> > >> > > > > > > messages. One concern would be that on the broker > >> side > >> > >>> > >> oversized > >> > >>> > >> > > > > messages > >> > >>> > >> > > > > > > will bring more memory pressure. With KIP-92, we > >> may > >> > >>> > mitigate > >> > >>> > >> > that, > >> > >>> > >> > > > but > >> > >>> > >> > > > > > the > >> > >>> > >> > > > > > > memory allocation for large messages may not be > >> very > >> > GC > >> > >>> > >> > friendly. I > >> > >>> > >> > > > > need > >> > >>> > >> > > > > > to > >> > >>> > >> > > > > > > think about this a little more. > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > Thanks, > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > Jiangjie (Becket) Qin > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > On Wed, Feb 22, 2017 at 8:57 PM, Jay Kreps < > >> > >>> > j...@confluent.io> > >> > >>> > >> > > wrote: > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > > Hey Becket, > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > I get the problem we want to solve with this, > >> but I > >> > >>> don't > >> > >>> > >> think > >> > >>> > >> > > > this > >> > >>> > >> > > > > is > >> > >>> > >> > > > > > > > something that makes sense as a user controlled > >> knob > >> > >>> that > >> > >>> > >> > > everyone > >> > >>> > >> > > > > > > sending > >> > >>> > >> > > > > > > > data to kafka has to think about. It is > >> basically a > >> > >>> bug, > >> > >>> > >> right? > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > First, as a technical question is it true that > >> using > >> > >>> the > >> > >>> > >> > > > uncompressed > >> > >>> > >> > > > > > > size > >> > >>> > >> > > > > > > > for batching actually guarantees that you > observe > >> > the > >> > >>> > >> limit? I > >> > >>> > >> > > > think > >> > >>> > >> > > > > > that > >> > >>> > >> > > > > > > > implies that compression always makes the > >> messages > >> > >>> > smaller, > >> > >>> > >> > > which i > >> > >>> > >> > > > > > think > >> > >>> > >> > > > > > > > usually true but is not guaranteed, right? e.g. > >> if > >> > >>> someone > >> > >>> > >> > > encrypts > >> > >>> > >> > > > > > their > >> > >>> > >> > > > > > > > data which tends to randomize it and then > enables > >> > >>> > >> > compressesion, > >> > >>> > >> > > it > >> > >>> > >> > > > > > could > >> > >>> > >> > > > > > > > slightly get bigger? > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > I also wonder if the rejected alternatives you > >> > >>> describe > >> > >>> > >> > couldn't > >> > >>> > >> > > be > >> > >>> > >> > > > > > made > >> > >>> > >> > > > > > > to > >> > >>> > >> > > > > > > > work: basically try to be a bit better at > >> estimation > >> > >>> and > >> > >>> > >> > recover > >> > >>> > >> > > > when > >> > >>> > >> > > > > > we > >> > >>> > >> > > > > > > > guess wrong. I don't think the memory usage > >> should > >> > be > >> > >>> a > >> > >>> > >> > problem: > >> > >>> > >> > > > > isn't > >> > >>> > >> > > > > > it > >> > >>> > >> > > > > > > > the same memory usage the consumer of that > topic > >> > would > >> > >>> > need? > >> > >>> > >> > And > >> > >>> > >> > > > > can't > >> > >>> > >> > > > > > > you > >> > >>> > >> > > > > > > > do the splitting and recompression in a > streaming > >> > >>> fashion? > >> > >>> > >> If > >> > >>> > >> > we > >> > >>> > >> > > an > >> > >>> > >> > > > > > make > >> > >>> > >> > > > > > > > the estimation rate low and the recovery cost > is > >> > just > >> > >>> ~2x > >> > >>> > >> the > >> > >>> > >> > > > normal > >> > >>> > >> > > > > > cost > >> > >>> > >> > > > > > > > for that batch that should be totally fine, > >> right? > >> > >>> (It's > >> > >>> > >> > > > technically > >> > >>> > >> > > > > > true > >> > >>> > >> > > > > > > > you might have to split more than once, but > since > >> > you > >> > >>> > halve > >> > >>> > >> it > >> > >>> > >> > > each > >> > >>> > >> > > > > > time > >> > >>> > >> > > > > > > I > >> > >>> > >> > > > > > > > think should you get a number of halvings that > is > >> > >>> > >> logarithmic > >> > >>> > >> > in > >> > >>> > >> > > > the > >> > >>> > >> > > > > > miss > >> > >>> > >> > > > > > > > size, which, with better estimation you'd hope > >> would > >> > >>> be > >> > >>> > >> super > >> > >>> > >> > > duper > >> > >>> > >> > > > > > > small). > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > Alternatively maybe we could work on the other > >> side > >> > >>> of the > >> > >>> > >> > > problem > >> > >>> > >> > > > > and > >> > >>> > >> > > > > > > try > >> > >>> > >> > > > > > > > to make it so that a small miss on message size > >> > isn't > >> > >>> a > >> > >>> > big > >> > >>> > >> > > > problem. > >> > >>> > >> > > > > I > >> > >>> > >> > > > > > > > think original issue was that max size and > fetch > >> > size > >> > >>> were > >> > >>> > >> > > tightly > >> > >>> > >> > > > > > > coupled > >> > >>> > >> > > > > > > > and the way memory in the consumer worked you > >> really > >> > >>> > wanted > >> > >>> > >> > fetch > >> > >>> > >> > > > > size > >> > >>> > >> > > > > > to > >> > >>> > >> > > > > > > > be as small as possible because you'd use that > >> much > >> > >>> memory > >> > >>> > >> per > >> > >>> > >> > > > > fetched > >> > >>> > >> > > > > > > > partition and the consumer would get stuck if > its > >> > >>> fetch > >> > >>> > size > >> > >>> > >> > > wasn't > >> > >>> > >> > > > > big > >> > >>> > >> > > > > > > > enough. I think we made some progress on that > >> issue > >> > >>> and > >> > >>> > >> maybe > >> > >>> > >> > > more > >> > >>> > >> > > > > > could > >> > >>> > >> > > > > > > be > >> > >>> > >> > > > > > > > done there so that a small bit of fuzziness > >> around > >> > the > >> > >>> > size > >> > >>> > >> > would > >> > >>> > >> > > > not > >> > >>> > >> > > > > > be > >> > >>> > >> > > > > > > an > >> > >>> > >> > > > > > > > issue? > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > -Jay > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > On Tue, Feb 21, 2017 at 12:30 PM, Becket Qin < > >> > >>> > >> > > becket....@gmail.com > >> > >>> > >> > > > > > >> > >>> > >> > > > > > > wrote: > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > > Hi folks, > >> > >>> > >> > > > > > > > > > >> > >>> > >> > > > > > > > > I would like to start the discussion thread > on > >> > >>> KIP-126. > >> > >>> > >> The > >> > >>> > >> > KIP > >> > >>> > >> > > > > > propose > >> > >>> > >> > > > > > > > > adding a new configuration to KafkaProducer > to > >> > allow > >> > >>> > >> batching > >> > >>> > >> > > > based > >> > >>> > >> > > > > > on > >> > >>> > >> > > > > > > > > uncompressed message size. > >> > >>> > >> > > > > > > > > > >> > >>> > >> > > > > > > > > Comments are welcome. > >> > >>> > >> > > > > > > > > > >> > >>> > >> > > > > > > > > The KIP wiki is following: > >> > >>> > >> > > > > > > > > https://cwiki.apache.org/confl > >> > >>> uence/display/KAFKA/KIP- > >> > >>> > >> > > > > > > > > 126+-+Allow+KafkaProducer+to+b > >> > >>> > >> atch+based+on+uncompressed+siz > >> > >>> > >> > e > >> > >>> > >> > > > > > > > > > >> > >>> > >> > > > > > > > > Thanks, > >> > >>> > >> > > > > > > > > > >> > >>> > >> > > > > > > > > Jiangjie (Becket) Qin > >> > >>> > >> > > > > > > > > > >> > >>> > >> > > > > > > > > >> > >>> > >> > > > > > > > >> > >>> > >> > > > > > > >> > >>> > >> > > > > > >> > >>> > >> > > > > >> > >>> > >> > > > > >> > >>> > >> > > > > >> > >>> > >> > > > -- > >> > >>> > >> > > > -Regards, > >> > >>> > >> > > > Mayuresh R. Gharat > >> > >>> > >> > > > (862) 250-7125 > >> > >>> > >> > > > > >> > >>> > >> > > > >> > >>> > >> > > >> > >>> > >> > > >> > >>> > >> > > >> > >>> > >> > -- > >> > >>> > >> > -Regards, > >> > >>> > >> > Mayuresh R. Gharat > >> > >>> > >> > (862) 250-7125 > >> > >>> > >> > > >> > >>> > >> > >> > >>> > > > >> > >>> > > > >> > >>> > > >> > >>> > >> > >> > >> > >> > >> > > > >> > > >> > > > > >
