+1 with one suggestion on the proposed metric. You should probably include the unit. So for e.g., max-compaction-delay-secs.
Joel On Tue, Nov 6, 2018 at 5:30 PM xiongqi wu <xiongq...@gmail.com> wrote: > bump > Xiongqi (Wesley) Wu > > > On Thu, Sep 27, 2018 at 4:20 PM xiongqi wu <xiongq...@gmail.com> wrote: > > > > > Thanks Eno, Brett, Dong, Guozhang, Colin, and Xiaohe for feedback. > > Can I have more feedback or VOTE on this KIP? > > > > > > Xiongqi (Wesley) Wu > > > > > > On Wed, Sep 19, 2018 at 10:52 AM xiongqi wu <xiongq...@gmail.com> wrote: > > > >> Any other votes or comments? > >> > >> Xiongqi (Wesley) Wu > >> > >> > >> On Tue, Sep 11, 2018 at 11:45 AM xiongqi wu <xiongq...@gmail.com> > wrote: > >> > >>> Yes, more votes and code review. > >>> > >>> Xiongqi (Wesley) Wu > >>> > >>> > >>> On Mon, Sep 10, 2018 at 11:37 PM Brett Rann <br...@zendesk.com.invalid > > > >>> wrote: > >>> > >>>> +1 (non binding) from on 0 then, and on the KIP. > >>>> > >>>> Where do we go from here? More votes? > >>>> > >>>> On Tue, Sep 11, 2018 at 5:34 AM Colin McCabe <cmcc...@apache.org> > >>>> wrote: > >>>> > >>>> > On Mon, Sep 10, 2018, at 11:44, xiongqi wu wrote: > >>>> > > Thank you for comments. I will use '0' for now. > >>>> > > > >>>> > > If we create topics through admin client in the future, we might > >>>> perform > >>>> > > some useful checks. (but the assumption is all brokers in the same > >>>> > cluster > >>>> > > have the same default configurations value, otherwise,it might > >>>> still be > >>>> > > tricky to do such cross validation check.) > >>>> > > >>>> > This isn't something that we might do in the future-- this is > >>>> something we > >>>> > are doing now. We already have Create Topic policies which are > >>>> enforced by > >>>> > the broker. Check KIP-108 and KIP-170 for details. This is one of > the > >>>> > motivations for getting rid of direct ZK access-- making sure that > >>>> these > >>>> > policies are applied. > >>>> > > >>>> > I agree that having different configurations on different brokers > can > >>>> be > >>>> > confusing and frustrating . That's why more configurations are being > >>>> made > >>>> > dynamic using KIP-226. Dynamic configurations are stored centrally > in > >>>> ZK, > >>>> > so they are the same on all brokers (modulo propagation delays). In > >>>> any > >>>> > case, this is a general issue, not specific to "create topics". > >>>> > > >>>> > cheers, > >>>> > Colin > >>>> > > >>>> > > >>>> > > > >>>> > > > >>>> > > Xiongqi (Wesley) Wu > >>>> > > > >>>> > > > >>>> > > On Mon, Sep 10, 2018 at 11:15 AM Colin McCabe <cmcc...@apache.org > > > >>>> > wrote: > >>>> > > > >>>> > > > I don't have a strong opinion. But I think we should probably be > >>>> > > > consistent with how segment.ms works, and just use 0. > >>>> > > > > >>>> > > > best, > >>>> > > > Colin > >>>> > > > > >>>> > > > > >>>> > > > On Wed, Sep 5, 2018, at 21:19, Brett Rann wrote: > >>>> > > > > OK thanks for that clarification. I see why you're > uncomfortable > >>>> > with 0 > >>>> > > > now. > >>>> > > > > > >>>> > > > > I'm not really fussed. I just prefer consistency in > >>>> configuration > >>>> > > > options. > >>>> > > > > > >>>> > > > > Personally I lean towards treating 0 and 1 similarly in that > >>>> > scenario, > >>>> > > > > because it favours the person thinking about setting the > >>>> > configurations, > >>>> > > > > and a person doesn't care about a 1ms edge case especially > when > >>>> the > >>>> > > > context > >>>> > > > > is the true minimum is tied to the log cleaner cadence. > >>>> > > > > > >>>> > > > > Introducing 0 to mean "disabled" because there is some > >>>> uniquness in > >>>> > > > > segment.ms not being able to be set to 0, reduces > configuration > >>>> > > > consistency > >>>> > > > > in favour of capturing a MS gap in an edge case that nobody > >>>> would > >>>> > ever > >>>> > > > > notice. For someone to understand why everywhere else -1 is > >>>> used to > >>>> > > > > disable, but here 0 is used, they would need to learn about > >>>> > segment.ms > >>>> > > > > having a 1ms minimum and then after learning would think "who > >>>> cares > >>>> > about > >>>> > > > > 1ms?" in this context. I would anyway :) > >>>> > > > > > >>>> > > > > my 2c anyway. Will again defer to majority. Curious which way > >>>> Colin > >>>> > falls > >>>> > > > > now. > >>>> > > > > > >>>> > > > > Don't want to spend more time on this though, It's well into > >>>> > > > bikeshedding > >>>> > > > > territory now. :) > >>>> > > > > > >>>> > > > > > >>>> > > > > > >>>> > > > > On Thu, Sep 6, 2018 at 1:31 PM xiongqi wu < > xiongq...@gmail.com> > >>>> > wrote: > >>>> > > > > > >>>> > > > > > I want to honor the minimum value of segment.ms (which is > >>>> 1ms) to > >>>> > > > force > >>>> > > > > > roll an active segment. > >>>> > > > > > So if we set "max.compaction.lag.ms" any value > 0, the > >>>> minimum of > >>>> > > > > > max.compaction.lag.ms and segment.ms will be used to seal > an > >>>> > active > >>>> > > > > > segment. > >>>> > > > > > > >>>> > > > > > If we set max.compaction.lag.ms to 0, the current > >>>> implementation > >>>> > will > >>>> > > > > > treat it as disabled. > >>>> > > > > > > >>>> > > > > > It is a little bit weird to treat max.compaction.lag=0 the > >>>> same as > >>>> > > > > > max.compaction.lag=1. > >>>> > > > > > > >>>> > > > > > There might be a reason why we set the minimum of > segment.ms > >>>> to 1, > >>>> > > > and I > >>>> > > > > > don't want to break this assumption. > >>>> > > > > > > >>>> > > > > > > >>>> > > > > > > >>>> > > > > > Xiongqi (Wesley) Wu > >>>> > > > > > > >>>> > > > > > > >>>> > > > > > On Wed, Sep 5, 2018 at 7:54 PM Brett Rann > >>>> > <br...@zendesk.com.invalid> > >>>> > > > > > wrote: > >>>> > > > > > > >>>> > > > > > > You're rolling a new segment if the condition is met > right? > >>>> So > >>>> > I'm > >>>> > > > > > > struggling to understand the relevance of segment.ms > here. > >>>> > Maybe an > >>>> > > > > > > example > >>>> > > > > > > would help my understanding: > >>>> > > > > > > > >>>> > > > > > > segment.ms=9999999 > >>>> > > > > > > *min.cleanable.dirty.ratio=1* > >>>> > > > > > > max.compaction.lag.ms=1 > >>>> > > > > > > > >>>> > > > > > > When a duplicate message comes in, after 1ms the topic > >>>> should be > >>>> > > > eligible > >>>> > > > > > > for compaction when the log compaction thread gets around > to > >>>> > > > evaluating > >>>> > > > > > the > >>>> > > > > > > topic. > >>>> > > > > > > > >>>> > > > > > > if we have > >>>> > > > > > > segment.ms=9999999 > >>>> > > > > > > *min.cleanable.dirty.ratio=1* > >>>> > > > > > > max.compaction.lag.ms=0 > >>>> > > > > > > > >>>> > > > > > > When a duplicate message comes in, after 0ms the topic > >>>> should be > >>>> > > > eligible > >>>> > > > > > > for compaction when the log compaction thread gets around > to > >>>> > > > evaluating > >>>> > > > > > the > >>>> > > > > > > topic. > >>>> > > > > > > > >>>> > > > > > > In both of those cases the change would mean a new segment > >>>> is > >>>> > rolled > >>>> > > > so > >>>> > > > > > the > >>>> > > > > > > new message would be part of the compaction task. 0 and 1 > >>>> are > >>>> > > > practically > >>>> > > > > > > the same meaning since neither is providing an actual > >>>> guarantee > >>>> > at > >>>> > > > such > >>>> > > > > > low > >>>> > > > > > > MS settings, but effectively tying it to both the > frequency > >>>> of > >>>> > the > >>>> > > > log > >>>> > > > > > > cleaner running and the priority of the given topic being > >>>> the > >>>> > highest > >>>> > > > > > > priority of all topics that are evaluated for cleaning on > >>>> the > >>>> > next > >>>> > > > cycle. > >>>> > > > > > > You've captured that nuance with careful "skipped" wording > >>>> in > >>>> > the KIP > >>>> > > > > > > here "controls > >>>> > > > > > > the max time interval a message/segment can be skipped for > >>>> log > >>>> > > > > > compaction". > >>>> > > > > > > > >>>> > > > > > > How is 0 different to 1, practically? And how is it > >>>> relating to > >>>> > > > > > segment.ms > >>>> > > > > > > ? > >>>> > > > > > > Is it that you're proposing to have 0 mean "use > segment.ms > >>>> > > > instead?" as > >>>> > > > > > a > >>>> > > > > > > kind of third option? > >>>> > > > > > > > >>>> > > > > > > > >>>> > > > > > > > >>>> > > > > > > On Thu, Sep 6, 2018 at 11:34 AM xiongqi wu < > >>>> xiongq...@gmail.com> > >>>> > > > wrote: > >>>> > > > > > > > >>>> > > > > > > > To make it clear, > >>>> > > > > > > > I don't against using -1 as disabled, but we need to > come > >>>> up > >>>> > with > >>>> > > > the > >>>> > > > > > > > meaning of "0". > >>>> > > > > > > > If "0" means immediate compaction, but the actual > >>>> compaction > >>>> > lag > >>>> > > > will > >>>> > > > > > be > >>>> > > > > > > > segment.ms. > >>>> > > > > > > > It has longer lag than setting the value to be half of > >>>> > segment.ms. > >>>> > > > > > > > We cannot provide "0" as max compaction lag. > >>>> > > > > > > > > >>>> > > > > > > > Here are two options. > >>>> > > > > > > > Option 1: > >>>> > > > > > > > Keep 0 as disabled > >>>> > > > > > > > Option 2: > >>>> > > > > > > > -1 (disabled), 0 (max compaction lag = segment.ms), and > >>>> > others. > >>>> > > > > > > > > >>>> > > > > > > > > >>>> > > > > > > > > >>>> > > > > > > > Xiongqi (Wesley) Wu > >>>> > > > > > > > > >>>> > > > > > > > > >>>> > > > > > > > On Wed, Sep 5, 2018 at 5:49 PM Brett Rann > >>>> > > > <br...@zendesk.com.invalid> > >>>> > > > > > > > wrote: > >>>> > > > > > > > > >>>> > > > > > > > > -1 is consistent as "special" with these settings for > >>>> > example: > >>>> > > > > > > > > > >>>> > > > > > > > > log.retention.bytes > >>>> > > > > > > > > socket.received.buffer.bytes > >>>> > > > > > > > > socket.send.buffer.bytes > >>>> > > > > > > > > queued.max.request.bytes > >>>> > > > > > > > > retention.bytes > >>>> > > > > > > > > retention.ms > >>>> > > > > > > > > > >>>> > > > > > > > > and acks. > >>>> > > > > > > > > > >>>> > > > > > > > > Where it may mean no limit, use OS defaults, max > (acks), > >>>> > etc. I > >>>> > > > don't > >>>> > > > > > > see > >>>> > > > > > > > > much convention of 0 meaning those things. > >>>> > > > > > > > > > >>>> > > > > > > > > There are some NULLs but it seems convetion there is > >>>> NULL is > >>>> > used > >>>> > > > > > where > >>>> > > > > > > > > there's another setting in the hierarchy that would be > >>>> used > >>>> > > > instead. > >>>> > > > > > > > > > >>>> > > > > > > > > > >>>> > > > > > > > > > >>>> > > > > > > > > > >>>> > > > > > > > > On Thu, Sep 6, 2018 at 10:42 AM Brett Rann < > >>>> > br...@zendesk.com> > >>>> > > > > > wrote: > >>>> > > > > > > > > > >>>> > > > > > > > > > If segment.ms can't be set to 0, then we're not > being > >>>> > > > consistent > >>>> > > > > > > > > > by using 0 for this new setting? I throw out -1 for > >>>> > > > consideration > >>>> > > > > > > > > > again :) > >>>> > > > > > > > > > > >>>> > > > > > > > > > On Thu, Sep 6, 2018 at 10:03 AM xiongqi wu < > >>>> > > > xiongq...@gmail.com> > >>>> > > > > > > > wrote: > >>>> > > > > > > > > > > >>>> > > > > > > > > >> Thanks. I will document after PR is merged. > >>>> > > > > > > > > >> > >>>> > > > > > > > > >> BTW, Kafka enforce the minimum of "segment.ms" to > >>>> 1, we > >>>> > > > cannot > >>>> > > > > > set > >>>> > > > > > > " > >>>> > > > > > > > > >> segment.ms" to 0. > >>>> > > > > > > > > >> > >>>> > > > > > > > > >> I also updated the title of this KIP. > >>>> > > > > > > > > >> > >>>> > > > > > > > > >> Xiongqi (Wesley) Wu > >>>> > > > > > > > > >> > >>>> > > > > > > > > >> > >>>> > > > > > > > > >> On Wed, Sep 5, 2018 at 4:34 PM Brett Rann > >>>> > > > > > <br...@zendesk.com.invalid > >>>> > > > > > > > > >>>> > > > > > > > > >> wrote: > >>>> > > > > > > > > >> > >>>> > > > > > > > > >> > I withdraw my comments on -1 since i'm in the > >>>> minority. > >>>> > :) > >>>> > > > Can > >>>> > > > > > we > >>>> > > > > > > > > >> > make sure 0 gets documented as meaning disabled > >>>> here: > >>>> > > > > > > > > >> > > >>>> https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs> > >>>> > > > > > <https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs>> > >>>> > > > > > > > <https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs> > >>>> > > > > > <https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs>>> > >>>> > > > > > > > > >> < > >>>> https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs> > >>>> > > > > > <https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs>> > >>>> > > > > > > > <https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs> > >>>> > > > > > <https://kafka.apache.org/documentation/#brokerconfigs > >>>> > <https://kafka.apache.org/documentation/#brokerconfigs>>>> ? > >>>> > > > > > > > > >> > And while there it would be good if segment.ms > is > >>>> > > > documented > >>>> > > > > > > > > >> > that 0 is disabled too. (there's some hierarchy > of > >>>> > configs > >>>> > > > for > >>>> > > > > > > that > >>>> > > > > > > > > too > >>>> > > > > > > > > >> > if its not set and null for others means > disabled!) > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > On Thu, Sep 6, 2018 at 4:44 AM xiongqi wu < > >>>> > > > xiongq...@gmail.com> > >>>> > > > > > > > > wrote: > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > > If we use 0 to indicate immediate compaction, > the > >>>> > > > compaction > >>>> > > > > > lag > >>>> > > > > > > > is > >>>> > > > > > > > > >> > > determined by segment.ms in worst case. If > >>>> segment.ms > >>>> > is > >>>> > > > 24 > >>>> > > > > > > > hours, > >>>> > > > > > > > > >> > > "immediate compaction" is a weaker guarantee > than > >>>> > setting > >>>> > > > any > >>>> > > > > > > > value > >>>> > > > > > > > > >> less > >>>> > > > > > > > > >> > > than 24 hours. By the definition of "max > >>>> compaction > >>>> > lag", > >>>> > > > we > >>>> > > > > > > > cannot > >>>> > > > > > > > > >> have > >>>> > > > > > > > > >> > > zero lag. So I use 0 to indicate "disable". > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > Xiongqi (Wesley) Wu > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > On Wed, Sep 5, 2018 at 8:34 AM Colin McCabe < > >>>> > > > > > cmcc...@apache.org > >>>> > > > > > > > > >>>> > > > > > > > > >> wrote: > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > > On Tue, Sep 4, 2018, at 22:11, Brett Rann > >>>> wrote: > >>>> > > > > > > > > >> > > > > > That's a fair point. We should make 0 = > >>>> > disable, to > >>>> > > > be > >>>> > > > > > > > > >> consistent > >>>> > > > > > > > > >> > > with > >>>> > > > > > > > > >> > > > > the other settings. > >>>> > > > > > > > > >> > > > > > >>>> > > > > > > > > >> > > > > -1 is used elsewhere for disable and when > >>>> seeing > >>>> > it > >>>> > > > in a > >>>> > > > > > > > config > >>>> > > > > > > > > >> it's > >>>> > > > > > > > > >> > > > clear > >>>> > > > > > > > > >> > > > > that it's a special meaning. 0 doesn't have > >>>> to > >>>> > mean > >>>> > > > > > instant, > >>>> > > > > > > > it > >>>> > > > > > > > > >> just > >>>> > > > > > > > > >> > > > means > >>>> > > > > > > > > >> > > > > as quickly as possible. I don't think 0 is > >>>> > intuitive > >>>> > > > for > >>>> > > > > > > > > disabled > >>>> > > > > > > > > >> and > >>>> > > > > > > > > >> > > it > >>>> > > > > > > > > >> > > > > will be confusing. I wasn't aware > segment.ms=0 > >>>> == > >>>> > > > > > disabled, > >>>> > > > > > > > > but I > >>>> > > > > > > > > >> > > think > >>>> > > > > > > > > >> > > > > that is also unintuitive. > >>>> > > > > > > > > >> > > > > >>>> > > > > > > > > >> > > > I think there is an argument for keeping > these > >>>> two > >>>> > > > > > > > configurations > >>>> > > > > > > > > >> > > > consistent, since they are so similar. I > agree > >>>> that > >>>> > 0 > >>>> > > > was an > >>>> > > > > > > > > >> > unfortunate > >>>> > > > > > > > > >> > > > choice., > >>>> > > > > > > > > >> > > > > >>>> > > > > > > > > >> > > > best, > >>>> > > > > > > > > >> > > > Colin > >>>> > > > > > > > > >> > > > > >>>> > > > > > > > > >> > > > > > >>>> > > > > > > > > >> > > > > On Wed, Sep 5, 2018 at 11:38 AM Colin > McCabe > >>>> < > >>>> > > > > > > > > cmcc...@apache.org> > >>>> > > > > > > > > >> > > wrote: > >>>> > > > > > > > > >> > > > > > >>>> > > > > > > > > >> > > > > > On Tue, Sep 4, 2018, at 17:47, xiongqi wu > >>>> wrote: > >>>> > > > > > > > > >> > > > > > > Colin, > >>>> > > > > > > > > >> > > > > > > Thank you for comments. > >>>> > > > > > > > > >> > > > > > > see my inline reply below. > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > Xiongqi (Wesley) Wu > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > On Tue, Sep 4, 2018 at 5:24 PM Colin > >>>> McCabe < > >>>> > > > > > > > > >> cmcc...@apache.org> > >>>> > > > > > > > > >> > > > wrote: > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > > Hi Xiongqi, > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > Thanks for this KIP. > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > The name seems a bit ambiguous. Our > >>>> > compaction > >>>> > > > > > > policies > >>>> > > > > > > > > are > >>>> > > > > > > > > >> > > already > >>>> > > > > > > > > >> > > > > > > > time-based, after all. It seems like > >>>> this > >>>> > > > change is > >>>> > > > > > > > > focused > >>>> > > > > > > > > >> > > around > >>>> > > > > > > > > >> > > > > > adding > >>>> > > > > > > > > >> > > > > > > > a “max.compaction.lag.ms." Perhaps > >>>> the KIP > >>>> > > > title > >>>> > > > > > > should > >>>> > > > > > > > > be > >>>> > > > > > > > > >> > > > something > >>>> > > > > > > > > >> > > > > > > > like "add maximum compaction lag > time"? > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > ==========> sure. I will change the > >>>> title. > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > > The active segment is forced to roll > >>>> when > >>>> > > > either " > >>>> > > > > > > > > >> > > > > > max.compaction.lag.ms" > >>>> > > > > > > > > >> > > > > > > > > or "segment.ms" (log.roll.ms and > >>>> > > > log.roll.hours) > >>>> > > > > > > has > >>>> > > > > > > > > >> > reached. > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > If the max.compaction.lag.ms is low, > >>>> it > >>>> > seems > >>>> > > > like > >>>> > > > > > > > > segments > >>>> > > > > > > > > >> > will > >>>> > > > > > > > > >> > > > be > >>>> > > > > > > > > >> > > > > > > > rolled very frequently. This can be a > >>>> > source of > >>>> > > > > > > problems > >>>> > > > > > > > > in > >>>> > > > > > > > > >> the > >>>> > > > > > > > > >> > > > > > cluster, > >>>> > > > > > > > > >> > > > > > > > since creating many different small > log > >>>> > segments > >>>> > > > > > > > consumes > >>>> > > > > > > > > a > >>>> > > > > > > > > >> > huge > >>>> > > > > > > > > >> > > > > > amount of > >>>> > > > > > > > > >> > > > > > > > cluster resources. Therefore, I would > >>>> > suggest > >>>> > > > > > adding a > >>>> > > > > > > > > >> > > broker-level > >>>> > > > > > > > > >> > > > > > > > configuration which allows us to set > a > >>>> > minimum > >>>> > > > value > >>>> > > > > > > for > >>>> > > > > > > > > >> > > > > > > > max.compaction.lag.ms. If we let > >>>> users set > >>>> > it > >>>> > > > on a > >>>> > > > > > > > > >> per-topic > >>>> > > > > > > > > >> > > > basis, > >>>> > > > > > > > > >> > > > > > > > someone could set a value of 1 ms or > >>>> > something, > >>>> > > > and > >>>> > > > > > > > cause > >>>> > > > > > > > > >> > chaos. > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > =========> this applies to > segment.ms > >>>> as > >>>> > well. > >>>> > > > > > Today > >>>> > > > > > > > > users > >>>> > > > > > > > > >> can > >>>> > > > > > > > > >> > > > set " > >>>> > > > > > > > > >> > > > > > > segment.ms" to a very low value, and > >>>> cause a > >>>> > > > frequent > >>>> > > > > > > > > >> rolling of > >>>> > > > > > > > > >> > > > active > >>>> > > > > > > > > >> > > > > > > segments. > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > Hi Xiongqi, > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > I agree that this is an existing problem > >>>> with > >>>> > > > > > segment.ms. > >>>> > > > > > > > > >> However, > >>>> > > > > > > > > >> > > > that > >>>> > > > > > > > > >> > > > > > doesn't mean that we shouldn't fix it. As > >>>> you > >>>> > noted, > >>>> > > > > > there > >>>> > > > > > > > > will > >>>> > > > > > > > > >> be > >>>> > > > > > > > > >> > > more > >>>> > > > > > > > > >> > > > > > interest in these topic-level retention > >>>> > settings as > >>>> > > > a > >>>> > > > > > > result > >>>> > > > > > > > > of > >>>> > > > > > > > > >> > GDPR. > >>>> > > > > > > > > >> > > > It > >>>> > > > > > > > > >> > > > > > seems likely that pre-existing problems > >>>> will > >>>> > cause > >>>> > > > more > >>>> > > > > > > > > trouble. > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > The fix seems relatively straightforward > >>>> here -- > >>>> > > > add a > >>>> > > > > > > > > >> broker-level > >>>> > > > > > > > > >> > > > > > minimum segment.ms that overrides > >>>> per-topic > >>>> > > > minimums. > >>>> > > > > > We > >>>> > > > > > > > can > >>>> > > > > > > > > >> also > >>>> > > > > > > > > >> > > fail > >>>> > > > > > > > > >> > > > > > with a helpful error message when someone > >>>> > attempts > >>>> > > > to > >>>> > > > > > set > >>>> > > > > > > an > >>>> > > > > > > > > >> > invalid > >>>> > > > > > > > > >> > > > > > configuration. > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > > In my option, the minimum of " > >>>> > > > max.compaction.lag.ms" > >>>> > > > > > > > should > >>>> > > > > > > > > >> be > >>>> > > > > > > > > >> > > > > > > based on the minimum of "segment.ms". > >>>> Since > >>>> > > > today the > >>>> > > > > > > > > >> minimum of > >>>> > > > > > > > > >> > > > > > segment.ms > >>>> > > > > > > > > >> > > > > > > is 1, "max.compaction.lag.ms" also > >>>> starts > >>>> > with > >>>> > > > 1. "0" > >>>> > > > > > > > means > >>>> > > > > > > > > >> > > > disable. I > >>>> > > > > > > > > >> > > > > > > can use -1 as disable, but it is hard > to > >>>> > define > >>>> > > > the > >>>> > > > > > > > meaning > >>>> > > > > > > > > >> of 0 > >>>> > > > > > > > > >> > > > because > >>>> > > > > > > > > >> > > > > > we > >>>> > > > > > > > > >> > > > > > > cannot just roll the active segment > >>>> > immediately. > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > That's a fair point. We should make 0 = > >>>> > disable, to > >>>> > > > be > >>>> > > > > > > > > >> consistent > >>>> > > > > > > > > >> > > with > >>>> > > > > > > > > >> > > > the > >>>> > > > > > > > > >> > > > > > other settings. > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > best, > >>>> > > > > > > > > >> > > > > > Colin > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > > -- Note that an alternative > >>>> configuration > >>>> > is to > >>>> > > > use > >>>> > > > > > -1 > >>>> > > > > > > > as > >>>> > > > > > > > > >> > > > "disabled" > >>>> > > > > > > > > >> > > > > > and > >>>> > > > > > > > > >> > > > > > > > 0 > >>>> > > > > > > > > >> > > > > > > > > as "immediate compaction". Because > >>>> > compaction > >>>> > > > lag > >>>> > > > > > is > >>>> > > > > > > > > still > >>>> > > > > > > > > >> > > > determined > >>>> > > > > > > > > >> > > > > > > > > based on min.compaction.lag and how > >>>> long > >>>> > to > >>>> > > > roll > >>>> > > > > > an > >>>> > > > > > > > > active > >>>> > > > > > > > > >> > > > segment, > >>>> > > > > > > > > >> > > > > > > > the > >>>> > > > > > > > > >> > > > > > > > > actual lag for compaction is > >>>> undetermined > >>>> > if > >>>> > > > we > >>>> > > > > > use > >>>> > > > > > > > "0". > >>>> > > > > > > > > >> On > >>>> > > > > > > > > >> > the > >>>> > > > > > > > > >> > > > other > >>>> > > > > > > > > >> > > > > > > > > hand, we can already set > >>>> > > > > > "min.cleanable.dirty.ratio" > >>>> > > > > > > > to > >>>> > > > > > > > > >> > achieve > >>>> > > > > > > > > >> > > > the > >>>> > > > > > > > > >> > > > > > > > same > >>>> > > > > > > > > >> > > > > > > > > goal. So here we choose "0" as > >>>> "disabled". > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > I would prefer -1 to be the invalid > >>>> setting. > >>>> > > > > > Treating > >>>> > > > > > > 0 > >>>> > > > > > > > > >> > > differently > >>>> > > > > > > > > >> > > > > > than > >>>> > > > > > > > > >> > > > > > > > 1 seems strange to me. > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > =====> see my previous comment, I am > >>>> not > >>>> > > > strongly > >>>> > > > > > > > against, > >>>> > > > > > > > > >> but > >>>> > > > > > > > > >> > 0 > >>>> > > > > > > > > >> > > is > >>>> > > > > > > > > >> > > > > > not a > >>>> > > > > > > > > >> > > > > > > valid configuration in my option. So I > >>>> use > >>>> > "0" as > >>>> > > > > > > disabled > >>>> > > > > > > > > >> state. > >>>> > > > > > > > > >> > > > > > > > >>>> > > > > > > > > >> > > > > > > best, > >>>> > > > > > > > > >> > > > > > > > Colin > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > > On Tue, Sep 4, 2018, at 15:04, > xiongqi > >>>> wu > >>>> > wrote: > >>>> > > > > > > > > >> > > > > > > > > Let's VOTE for this KIP. > >>>> > > > > > > > > >> > > > > > > > > KIP: > >>>> > > > > > > > > >> > > > > > > > > > >>>> > > > > > > > > > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>> > >>>> > > > > > > > > >> < > >>>> > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>>> > >>>> > > > > > > > > >> > > < > >>>> > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>> > >>>> > > > > > > > > >> < > >>>> > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>>>> > >>>> > > > > > > > > >> > > > > > < > >>>> > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>> > >>>> > > > > > > > > >> < > >>>> > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>>> > >>>> > > > > > > > > >> > > < > >>>> > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>> > >>>> > > > > > > > > >> < > >>>> > https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>> > >>>> > > > > > > > < > >>>> https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354> > >>>> > > > > > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354 > >>>> > <https://cwiki.apache.org/confluence/display/KAFKA/KIP-354>>>>>> > >>>> > > > > > > > > >> > > > > > > > > > %3A+Time-based+log+compaction+policy > >>>> > > > > > > > > >> > > > > > > > > > >>>> > > > > > > > > >> > > > > > > > > Implementation: > >>>> > > > > > > > > >> > > > > > > > > > >>>> > > > > > > > > >> > > > > > > > > > >>>> https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>> > >>>> > > > > > > > > >> <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>>> > >>>> > > > > > > > > >> > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>> > >>>> > > > > > > > > >> <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>>>> > >>>> > > > > > > > > >> > > > > > < > https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>> > >>>> > > > > > > > > >> <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>>> > >>>> > > > > > > > > >> > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>> > >>>> > > > > > > > > >> <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>> > >>>> > > > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611> > >>>> > > > > > <https://github.com/apache/kafka/pull/5611 > >>>> > <https://github.com/apache/kafka/pull/5611>>>>>> > >>>> > > > > > > > > >> > > > > > > > > > >>>> > > > > > > > > >> > > > > > > > > > >>>> > > > > > > > > >> > > > > > > > > > >>>> > > > > > > > > >> > > > > > > > > Xiongqi (Wesley) Wu > >>>> > > > > > > > > >> > > > > > > > > >>>> > > > > > > > > >> > > > > > > >>>> > > > > > > > > >> > > > > >>>> > > > > > > > > >> > > > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > -- > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > Brett Rann > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > Senior DevOps Engineer > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > Zendesk International Ltd > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > 395 Collins Street, Melbourne VIC 3000 Australia > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > Mobile: +61 (0) 418 826 017 > >>>> > > > > > > > > >> > > >>>> > > > > > > > > >> > >>>> > > > > > > > > > > >>>> > > > > > > > > > > >>>> > > > > > > > > > -- > >>>> > > > > > > > > > > >>>> > > > > > > > > > Brett Rann > >>>> > > > > > > > > > > >>>> > > > > > > > > > Senior DevOps Engineer > >>>> > > > > > > > > > > >>>> > > > > > > > > > > >>>> > > > > > > > > > Zendesk International Ltd > >>>> > > > > > > > > > > >>>> > > > > > > > > > 395 Collins Street, Melbourne VIC 3000 Australia > >>>> > > > > > > > > > > >>>> > > > > > > > > > Mobile: +61 (0) 418 826 017 > >>>> > > > > > > > > > > >>>> > > > > > > > > > >>>> > > > > > > > > > >>>> > > > > > > > > -- > >>>> > > > > > > > > > >>>> > > > > > > > > Brett Rann > >>>> > > > > > > > > > >>>> > > > > > > > > Senior DevOps Engineer > >>>> > > > > > > > > > >>>> > > > > > > > > > >>>> > > > > > > > > Zendesk International Ltd > >>>> > > > > > > > > > >>>> > > > > > > > > 395 Collins Street, Melbourne VIC 3000 Australia > >>>> > > > > > > > > > >>>> > > > > > > > > Mobile: +61 (0) 418 826 017 > >>>> > > > > > > > > > >>>> > > > > > > > > >>>> > > > > > > > >>>> > > > > > > >>>> > > > > >>>> > > >>>> > >>> >