> > For some users canonical savepoints are prohibitively expensive either to > take or to recover from. To a point where the system is unable to complete > them before some timeout/failure happens.
I'd say the same logic applies for re-scaling the job from the RDB based checkpoint / savepoint. I'm still not positive that we can solve the re-scaling performance without disrupting the backward compatibility. Just for more context, this is something we need to solve for getting reactive mode / auto-scaling broadly adopted. Overall, I like the idea of making the migration path as smooth as possible for end users as this may allow for faster adoption of new Flink versions, but there are new problems this might introduce and we should be aware of them. D. On Wed, Jan 19, 2022 at 9:04 AM Piotr Nowojski <pnowoj...@apache.org> wrote: > Hi David, > > I didn't mean "best effort". It's just that we would be relaying on a 3rd > party system, which quoting [1]: > > > RocksDB goes to great lengths to ensure data remains both forward- and > backward-compatible > > But it's still a 3rd party system that we do not control. It's the same > with KafkaClient for example. Yes, it's supposed to be backward/forward > compatible, but we do not control it. Moreover, even for things that we do > control, and we claim that they are "stable" "public" and we do guarantee > backward compatibility, we might break compatibility from time to time. We > did things like that in the past if there was no way of fixing a bug > without some breaking change. > > > Why are the canonical savepoints not good enough for supporting minor > version upgrades? > > For some users canonical savepoints are prohibitively expensive either to > take or to recover from. To a point where the system is unable to complete > them before some timeout/failure happens. > > Besides, I would really like for the sake of simplicity (from the user's > perspective) to keep both canonical and native savepoints as close together > as possible. > > Best, > Piotrek > > [1] https://dl.acm.org/doi/fullHtml/10.1145/3483840 > > > wt., 18 sty 2022 o 19:27 David Morávek <d...@apache.org> napisał(a): > > > Hi Piotr, > > > > thanks for following up on this, > > > > Regarding the RocksDB incompatibility, I think we can claim that Flink > > > version upgrades are/will be supported. If ever we need to break the > > > backward compatibility via bumping RocksDB version in a such way, that > > > RocksDB won't be able to provide that compatibility, we will need to > make > > > this a prominent notice in the release notes. > > > > > > I'm still not sure about this. Would that mean giving up flexibility for > > the future improvements to the state backend infrastructure? For example > > I'm experimenting along the lines of switching range partitioning for > > consistent hashing to speed up re-scaling. Just this simple change (or > any > > other change to layout in general) would make the checkpoints > incompatible > > or it would involve non-trivial effort to support migration from older > > versions. > > > > Maybe it's just about how it's phrased, what you're suggesting fits > > somewhere between "best effort compatibility" & "guaranteed > compatibility". > > If we say it's best effort ("we're free to change anything, but this > > shouldn't be done blindly"), then it should provide the flexibility we > > need. > > > > Why are the canonical savepoints not good enough for supporting minor > > version upgrades? Yes with some larger state this might be time > consuming, > > but wouldn't these use-cases benefit more from further optimizations to > the > > state backend? Also how often are users doing these updates (I'd say max > > twice a year if they follow-up the release cycle)? > > > > Best, > > D. > > > > On Tue, Jan 18, 2022 at 3:51 PM Piotr Nowojski <pnowoj...@apache.org> > > wrote: > > > > > Hi All, > > > > > > Yu, sorry I was somehow confused about the configuration. I've changed > > > the FLIP as you sugested. > > > > > > Yu/Yun Tang: > > > > > > Regarding the RocksDB incompatibility, I think we can claim that Flink > > > version upgrades are/will be supported. If ever we need to break the > > > backward compatibility via bumping RocksDB version in a such way, that > > > RocksDB won't be able to provide that compatibility, we will need to > make > > > this a prominent notice in the release notes. > > > > > > > I have used the State Processor API with aligned, full checkpoints. > > There > > > it has worked just fine. > > > > > > Thanks for this information. > > > > > > > 0) What exactly does the "State Processor API" row mean? Is it: Can > it > > be > > > > read by the State Processor API? Can it be written by the State > > Processor > > > > API? Both? Something else? > > > > > > Good question. I'm not sure how State Processor API is working. Can > > someone > > > help answer what we guarantee/support right now and what we can > > > reasonably support? > > > > > > > 1) and 2) > > > > > > I guess you are simply in favour of the 2nd proposal? So > > > > > > * rescaling > > > * Job upgrade w/o changing graph shape and record types > > > * Flink bug/patch (1.14.x → 1.14.y) version upgrade > > > > > > + Flink minor (1.x → 1.y) version upgrade > > > > > > which I think is important for the native savepoint to be truly > > savepoints. > > > > > > > 3) Should "Job upgrade w/o changing graph shape and record types" be > > > split? I guess "record types" is only relevant for unaligned > checkpoints. > > > > > > Shape of the job graph is also an issue with unaligned checkpoints. > > > Changing record types/serialisation causes obvious problems with the > > > in-flight records, but if you change job graph via for example changing > > > type of the network connection (like random -> broadcast, keyed -> non > > > keyed), or remove some operators, we also have problems with the > > in-flight > > > records in the affected connections. > > > > > > > 4) > > > > > > I think configuration change should be always supported. If you think > > > that's important, I can add this to the documentation/FLIP proposal as > a > > > separate row. > > > > > > > 5) Do the guarantees that a Savepoint/Checkpoint provide change when > > > > generalized incremental checkpoints [1] are enabled? My understanding > > is: > > > > No, the same guarantees apply. > > > > > > This will be more tricky and it will highly depend on the FLIP-158 > > > implementation. > > > > > > Yun: > > > > > > > 1. From my understanding, native savepoint appears much closer to > > > current alignment checkpoint. What's their difference? > > > > > > Technically there would be no difference, but we might decide to limit > > what > > > we officially support, to allow us easier changes in the future. Just > as > > > for the most part so far between savepoint and checkpoints there was > very > > > little difference. For us, as developers, the fewer things we > officially > > > support and claim are stable, the better. > > > > > > > 2. If self-contained and relocatable are the most important > > difference, > > > why not include them in the proposal table? > > > > > > Good point. I will add this. > > > > > > > What does "Job full upgrade" means? > > > > > > I have clarified it to: > > > > Arbitrary job upgrade (changed graph shape/record types) > > > > > > It's an arbitrary job change. Anything that doesn't fall into the > second > > > category "Job upgrade w/o changing graph shape and record types" > > > > > > Best, > > > Piotrek > > > > > > pon., 17 sty 2022 o 11:25 Yun Tang <myas...@live.com> napisał(a): > > > > > > > Hi everyone, > > > > > > > > Thanks for Piotr to drive this topic. > > > > > > > > I have several questions on this FLIP. > > > > > > > > 1. From my understanding, native savepoint appears much closer to > > > > current alignment checkpoint. What's their difference? > > > > 2. If self-contained and relocatable are the most important > > > difference, > > > > why not include them in the proposal table? > > > > > > > > 1. What does "Job full upgrade" means? > > > > > > > > For the question of RocksDB upgrading, this depends on the backwards > > > > compatibility [1], and it proves to be very well as the documentation > > > said. > > > > > > > > > > > > [1] > > > > > > > > > > https://github.com/facebook/rocksdb/wiki/RocksDB-Compatibility-Between-Different-Releases > > > > > > > > Best， > > > > Yun Tang > > > > > > > > > > > > > > > > ________________________________ > > > > From: Konstantin Knauf <konstan...@ververica.com> > > > > Sent: Friday, January 14, 2022 20:39 > > > > To: dev <dev@flink.apache.org>; Seth Wiesman <s...@ververica.com>; > > Nico > > > > Kruber <n...@ververica.com>; dander...@apache.org < > > dander...@apache.org> > > > > Subject: Re: [DISCUSS] FLIP-203: Incremental savepoints > > > > > > > > Hi everyone, > > > > > > > > Thank you, Piotr. Please find my thoughts on the topic below: > > > > > > > > 0) What exactly does the "State Processor API" row mean? Is it: Can > it > > be > > > > read by the State Processor API? Can it be written by the State > > Processor > > > > API? Both? Something else? > > > > > > > > 1) If we take the assumption from FLIP-193 "that ownership should be > > the > > > > only difference between Checkpoints and Savepoints.", we would need > to > > > work > > > > in the direction of "Proposal 2". The distinction would then be the > > > > following: > > > > > > > > * Canonical Savepoint = Guarantees A > > > > * Canonical Checkpoint = Guarantees A (in theory; does not exist) > > > > * Aligned, Native Checkpoint = Guarantees B > > > > * Aligned, Native Savepoint = Guarantees B > > > > * Unaligned, Native Checkpoint = Guarantees C > > > > * Unaligned, Native Savepoint = Guarantees C (if this would exist in > > the > > > > future) > > > > > > > > I think it is important to make this matrix not too complicated like: > > > there > > > > are 8 different sets of guarantees depending on all kinds of more or > > less > > > > well-known configuration options. > > > > > > > > 2) With respect to the concrete guarantees, I believe, it's important > > > that > > > > we can cover all important use cases in "green", so that users can > rely > > > on > > > > official, tested behavior in regular operations. In my experience > this > > > > includes manual recovery of a Job from a retained checkpoint. I would > > > argue > > > > that most users operating a long-running, stateful Apache Flink > > > application > > > > have been in the situation, where a graceful "stop" was not possible > > > > anymore, because the Job was unable to take a Savepoint. This could > be, > > > > because the Job is frequently restarting (e.g. poison pill) or > because > > it > > > > fails on taking the Savepoint itself for some reason (e.g. unable to > > > commit > > > > a transaction to an external system). The solution strategy in this > > > > scenario is to cancel the job, make some changes to the Job or > > > > configuration that fix the problem and restore from the last > successful > > > > (retained) checkpoint. I think the following changes would need to be > > > > officially supported for Native Checkpoints/Savepoint (Guarantees B, > > > > ideally also Guarantees C), in order to fix a Job in most of these > > cases. > > > > > > > > * rescaling > > > > * Job upgrade w/o changing graph shape and record types > > > > * Flink bug/patch (1.14.x → 1.14.y) version upgrade > > > > > > > > I would be very interested to hear from users as well as people like > > > Seth, > > > > Nico or David (cc), who work with many users, what in their > experience > > > > would be needed here. > > > > > > > > 3) Should "Job upgrade w/o changing graph shape and record types" be > > > split? > > > > I guess "record types" is only relevant for unaligned checkpoints. > > > > > > > > 4) Does it make sense to consider Flink configuration changes besides > > the > > > > statebackend type as another row? Maybe split by "pipeline.*" > options, > > > > "execution.*" options, and whichever other categories would make > sense. > > > > Just to give a few examples: it should be *officially* supported to > > take > > > a > > > > native retained checkpoint and restart a the Job with a > > > > pipeline.auto-watermark-interval and different high-availability > > > > configurations > > > > > > > > 5) Do the guarantees that a Savepoint/Checkpoint provide change when > > > > generalized incremental checkpoints [1] are enabled? My understanding > > is: > > > > No, the same guarantees apply. > > > > > > > > Cheers and thank you, > > > > > > > > Konstantin > > > > > > > > [1] > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-158%3A+Generalized+incremental+checkpoints?src=contextnavpagetreemode > > > > > > > > On Fri, Jan 14, 2022 at 11:24 AM David Anderson < > dander...@apache.org> > > > > wrote: > > > > > > > > > > I have a very similar question to State Processor API. Is it the > > same > > > > > scenario in this case? > > > > > > Should it also be working with checkpoints but might be just > > > untested? > > > > > > > > > > I have used the State Processor API with aligned, full checkpoints. > > > There > > > > > it has worked just fine. > > > > > > > > > > David > > > > > > > > > > On Thu, Jan 13, 2022 at 12:40 PM Piotr Nowojski < > > pnowoj...@apache.org> > > > > > wrote: > > > > > > > > > > > Hi, > > > > > > > > > > > > Thanks for the comments and questions. Starting from the top: > > > > > > > > > > > > Seth: good point about schema evolution. Actually, I have a very > > > > similar > > > > > > question to State Processor API. Is it the same scenario in this > > > case? > > > > > > Should it also be working with checkpoints but might be just > > > untested? > > > > > > > > > > > > And next question, should we commit to supporting those two > things > > > > (State > > > > > > Processor API and schema evolution) for native savepoints? What > > about > > > > > > aligned checkpoints? (please check [1] for that). > > > > > > > > > > > > Yu Li: 1, 2 and 4 done. > > > > > > > > > > > > > 3. How about changing the description of "the default > > configuration > > > > of > > > > > > the > > > > > > > checkpoints will be used to determine whether the savepoint > > should > > > be > > > > > > > incremental or not" to something like "the > > > > `state.backend.incremental` > > > > > > > setting now denotes the type of native format snapshot and will > > > take > > > > > > effect > > > > > > > for both checkpoint and savepoint (with native type)", to > prevent > > > > > concept > > > > > > > confusion between checkpoint and savepoint? > > > > > > > > > > > > Is `state.backend.incremental` the only configuration parameter > > that > > > > can > > > > > be > > > > > > used in this context? I would guess not? What about for example > > > > > > "state.storage.fs.memory-threshold" or all of the Advanced > RocksDB > > > > State > > > > > > Backends Options [2]? > > > > > > > > > > > > David: > > > > > > > > > > > > > does this mean that we need to keep the checkpoints compatible > > > across > > > > > > minor > > > > > > > versions? Or can we say, that the minor version upgrades are > only > > > > > > > guaranteed with canonical savepoints? > > > > > > > > > > > > Good question. Frankly I was always assuming that this is > > implicitly > > > > > given. > > > > > > Otherwise users would not be able to recover jobs that are > failing > > > > > because > > > > > > of bugs in Flink. But I'm pretty sure that was never explicitly > > > stated. > > > > > > > > > > > > As Konstantin suggested, I've written down the pre-existing > > > guarantees > > > > of > > > > > > checkpoints and savepoints followed by two proposals on how they > > > should > > > > > be > > > > > > changed [1]. Could you take a look? > > > > > > > > > > > > I'm especially unsure about the following things: > > > > > > a) What about RocksDB upgrades? If we bump RocksDB version > between > > > > Flink > > > > > > versions, do we support recovering from a native format snapshot > > > > > > (incremental checkpoint)? > > > > > > b) State Processor API - both pre-existing and what do we want to > > > > provide > > > > > > in the future > > > > > > c) Schema Evolution - both pre-existing and what do we want to > > > provide > > > > in > > > > > > the future > > > > > > > > > > > > Best, > > > > > > Piotrek > > > > > > > > > > > > [1] > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-203%3A+Incremental+savepoints#FLIP203:Incrementalsavepoints-Checkpointvssavepointguarantees > > > > > > [2] > > > > > > > > > > > > > > > > > > > > > > > > > > > https://nightlies.apache.org/flink/flink-docs-master/docs/deployment/config/#advanced-rocksdb-state-backends-options > > > > > > > > > > > > wt., 11 sty 2022 o 09:45 Konstantin Knauf <kna...@apache.org> > > > > > napisał(a): > > > > > > > > > > > > > Hi Piotr, > > > > > > > > > > > > > > would it be possible to provide a table that shows the > > > > > > > compatibility guarantees provided by the different snapshots > > going > > > > > > forward? > > > > > > > Like type of change (Topology. State Schema, Parallelism, ..) > in > > > one > > > > > > > dimension, and type of snapshot as the other dimension. Based > on > > > > that, > > > > > it > > > > > > > would be easier to discuss those guarantees, I believe. > > > > > > > > > > > > > > Cheers, > > > > > > > > > > > > > > Konstantin > > > > > > > > > > > > > > On Mon, Jan 3, 2022 at 9:11 AM David Morávek <d...@apache.org> > > > > wrote: > > > > > > > > > > > > > > > Hi Piotr, > > > > > > > > > > > > > > > > does this mean that we need to keep the checkpoints > compatible > > > > across > > > > > > > minor > > > > > > > > versions? Or can we say, that the minor version upgrades are > > only > > > > > > > > guaranteed with canonical savepoints? > > > > > > > > > > > > > > > > My concern is especially if we'd want to change layout of the > > > > > > checkpoint. > > > > > > > > > > > > > > > > D. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Dec 29, 2021 at 5:19 AM Yu Li <car...@gmail.com> > > wrote: > > > > > > > > > > > > > > > > > Thanks for the proposal Piotr! Overall I'm +1 for the idea, > > and > > > > > below > > > > > > > are > > > > > > > > > my two cents: > > > > > > > > > > > > > > > > > > 1. How about adding a "Term Definition" section and clarify > > > what > > > > > > > "native > > > > > > > > > format" (the "native" data persistence format of the > current > > > > state > > > > > > > > backend) > > > > > > > > > and "canonical format" (the "uniform" format that supports > > > > > switching > > > > > > > > state > > > > > > > > > backends) means? > > > > > > > > > > > > > > > > > > 2. IIUC, currently the FLIP proposes to only support > > > incremental > > > > > > > > savepoint > > > > > > > > > with native format, and there's no plan to add such support > > for > > > > > > > canonical > > > > > > > > > format, right? If so, how about writing this down > explicitly > > in > > > > the > > > > > > > FLIP > > > > > > > > > doc, maybe in a "Limitations" section, plus the fact that > > > > > > > > > `HashMapStateBackend` cannot support incremental savepoint > > > before > > > > > > > > FLIP-151 > > > > > > > > > is done? (side note: @Roman just a kindly reminder, that > > please > > > > > take > > > > > > > > > FLIP-203 into account when implementing FLIP-151) > > > > > > > > > > > > > > > > > > 3. How about changing the description of "the default > > > > configuration > > > > > > of > > > > > > > > the > > > > > > > > > checkpoints will be used to determine whether the savepoint > > > > should > > > > > be > > > > > > > > > incremental or not" to something like "the > > > > > > `state.backend.incremental` > > > > > > > > > setting now denotes the type of native format snapshot and > > will > > > > > take > > > > > > > > effect > > > > > > > > > for both checkpoint and savepoint (with native type)", to > > > prevent > > > > > > > concept > > > > > > > > > confusion between checkpoint and savepoint? > > > > > > > > > > > > > > > > > > 4. How about putting the notes of behavior change (the > > default > > > > type > > > > > > of > > > > > > > > > savepoint will be changed to `native` in the future, and by > > > then > > > > > the > > > > > > > > taken > > > > > > > > > savepoint cannot be used to switch state backends by > default) > > > to > > > > a > > > > > > more > > > > > > > > > obvious place, for example moving from the "CLI" section to > > the > > > > > > > > > "Compatibility" section? (although it will only happen in > > 1.16 > > > > > > release > > > > > > > > > based on the proposed plan) > > > > > > > > > > > > > > > > > > And all above suggestions apply for our user-facing > document > > > > after > > > > > > the > > > > > > > > FLIP > > > > > > > > > is (partially or completely, accordingly) done, if taken > > > (smile). > > > > > > > > > > > > > > > > > > Best Regards, > > > > > > > > > Yu > > > > > > > > > > > > > > > > > > > > > > > > > > > On Tue, 21 Dec 2021 at 22:23, Seth Wiesman < > > > sjwies...@gmail.com> > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > >> AFAIK state schema evolution should work both for > native > > > and > > > > > > > > canonical > > > > > > > > > > >> savepoints. > > > > > > > > > > > > > > > > > > > > Schema evolution does technically work for both formats, > it > > > > > happens > > > > > > > > after > > > > > > > > > > the code paths have been unified, but the community has > up > > > > until > > > > > > this > > > > > > > > > point > > > > > > > > > > considered that an unsupported feature. From my > perspective > > > > > making > > > > > > > this > > > > > > > > > > supported could be as simple as adding test coverage but > > > that's > > > > > an > > > > > > > > active > > > > > > > > > > decision we'd need to make. > > > > > > > > > > > > > > > > > > > > On Tue, Dec 21, 2021 at 7:43 AM Piotr Nowojski < > > > > > > pnowoj...@apache.org > > > > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > Hi Konstantin, > > > > > > > > > > > > > > > > > > > > > > > In this context: will the native format support state > > > > schema > > > > > > > > > evolution? > > > > > > > > > > > If > > > > > > > > > > > > not, I am not sure, we can let the format default to > > > > native. > > > > > > > > > > > > > > > > > > > > > > AFAIK state schema evolution should work both for > native > > > and > > > > > > > > canonical > > > > > > > > > > > savepoints. > > > > > > > > > > > > > > > > > > > > > > Regarding what is/will be supported we will document as > > > part > > > > of > > > > > > > this > > > > > > > > > > > FLIP-203. But it's not as simple as just the difference > > > > between > > > > > > > > native > > > > > > > > > > and > > > > > > > > > > > canonical formats. > > > > > > > > > > > > > > > > > > > > > > Best, Piotrek > > > > > > > > > > > > > > > > > > > > > > pon., 20 gru 2021 o 14:28 Konstantin Knauf < > > > > kna...@apache.org> > > > > > > > > > > napisał(a): > > > > > > > > > > > > > > > > > > > > > > > Hi Piotr, > > > > > > > > > > > > > > > > > > > > > > > > Thanks a lot for starting the discussion. Big +1. > > > > > > > > > > > > > > > > > > > > > > > > In my understanding, this FLIP introduces the > snapshot > > > > format > > > > > > as > > > > > > > a > > > > > > > > > > > *really* > > > > > > > > > > > > user facing concept. IMO it is important that we > > document > > > > > > > > > > > > > > > > > > > > > > > > a) that it is not longer the checkpoint/savepoint > > > > > > characteristics > > > > > > > > > that > > > > > > > > > > > > determines the kind of changes that a snapshots > allows > > > > (user > > > > > > > code, > > > > > > > > > > state > > > > > > > > > > > > schema evolution, topology changes), but now this > > > becomes a > > > > > > > > property > > > > > > > > > of > > > > > > > > > > > the > > > > > > > > > > > > format regardless of whether this is a snapshots or a > > > > > > checkpoint > > > > > > > > > > > > b) the exact changes that each format allows (code, > > state > > > > > > schema, > > > > > > > > > > > topology, > > > > > > > > > > > > state backend, max parallelism) > > > > > > > > > > > > > > > > > > > > > > > > In this context: will the native format support state > > > > schema > > > > > > > > > evolution? > > > > > > > > > > > If > > > > > > > > > > > > not, I am not sure, we can let the format default to > > > > native. > > > > > > > > > > > > > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > > > > > > > > > > Konstantin > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Mon, Dec 20, 2021 at 2:09 PM Piotr Nowojski < > > > > > > > > pnowoj...@apache.org > > > > > > > > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > Hi devs, > > > > > > > > > > > > > > > > > > > > > > > > > > I would like to start a discussion about a > previously > > > > > > announced > > > > > > > > > > follow > > > > > > > > > > > up > > > > > > > > > > > > > of the FLIP-193 [1], namely allowing savepoints to > be > > > in > > > > > > native > > > > > > > > > > format > > > > > > > > > > > > and > > > > > > > > > > > > > incremental. The changes do not seem invasive. The > > full > > > > > > > proposal > > > > > > > > is > > > > > > > > > > > > > written down as FLIP-203: Incremental savepoints > [2]. > > > > > Please > > > > > > > > take a > > > > > > > > > > > look, > > > > > > > > > > > > > and let me know what you think. > > > > > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > > > > > Piotrek > > > > > > > > > > > > > > > > > > > > > > > > > > [1] > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-193%3A+Snapshots+ownership > > > > > > > > > > > > > [2] > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-203%3A+Incremental+savepoints#FLIP203:Incrementalsavepoints-Semantic > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > > > > > > > > > > > > > > > > > Konstantin Knauf > > > > > > > > > > > > > > > > > > > > > > > > https://twitter.com/snntrable > > > > > > > > > > > > > > > > > > > > > > > > https://github.com/knaufk > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > > > > > > > Konstantin Knauf > > > > > > > > > > > > > > https://twitter.com/snntrable > > > > > > > > > > > > > > https://github.com/knaufk > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > Konstantin Knauf | Head of Product > > > > > > > > +49 160 91394525 > > > > > > > > > > > > Follow us @VervericaData Ververica <https://www.ververica.com/> > > > > > > > > > > > > -- > > > > > > > > Join Flink Forward <https://flink-forward.org/> - The Apache Flink > > > > Conference > > > > > > > > Stream Processing | Event Driven | Real Time > > > > > > > > -- > > > > > > > > Ververica GmbH | Invalidenstrasse 115, 10115 Berlin, Germany > > > > > > > > -- > > > > Ververica GmbH > > > > Registered at Amtsgericht Charlottenburg: HRB 158244 B > > > > Managing Directors: Karl Anton Wehner, Holger Temme, Yip Park Tung > > Jason, > > > > Jinwei (Kevin) Zhang > > > > > > > > > >
