[jira] [Created] (KAFKA-10642) Expose the real stack trace if any exception occurred during SSL Client Trust Verification in extension
Senthilnathan Muthusamy created KAFKA-10642: --- Summary: Expose the real stack trace if any exception occurred during SSL Client Trust Verification in extension Key: KAFKA-10642 URL: https://issues.apache.org/jira/browse/KAFKA-10642 Project: Kafka Issue Type: Bug Components: clients Affects Versions: 2.5.1, 2.6.0, 2.4.1, 2.5.0, 2.3.1, 2.4.0, 2.3.0 Reporter: Senthilnathan Muthusamy Assignee: Senthilnathan Muthusamy Fix For: 2.7.0 If there is any exception occurred in the custom implementation of client trust verification (i.e. using security.provider), the inner exception is suppressed or hidden and not logged to the log file... Below is an example stack trace not showing actual exception from the extension/custom implementation. [2020-05-13 14:30:26,892] ERROR [KafkaServer id=423810470] Fatal error during KafkaServer startup. Prepare to shutdown (kafka.server.KafkaServer)[2020-05-13 14:30:26,892] ERROR [KafkaServer id=423810470] Fatal error during KafkaServer startup. Prepare to shutdown (kafka.server.KafkaServer) org.apache.kafka.common.KafkaException: org.apache.kafka.common.config.ConfigException: Invalid value java.lang.RuntimeException: Delegated task threw Exception/Error for configuration A client SSLEngine created with the provided settings can't connect to a server SSLEngine created with those settings. at org.apache.kafka.common.network.SslChannelBuilder.configure(SslChannelBuilder.java:71) at org.apache.kafka.common.network.ChannelBuilders.create(ChannelBuilders.java:146) at org.apache.kafka.common.network.ChannelBuilders.serverChannelBuilder(ChannelBuilders.java:85) at kafka.network.Processor.(SocketServer.scala:753) at kafka.network.SocketServer.newProcessor(SocketServer.scala:394) at kafka.network.SocketServer.$anonfun$addDataPlaneProcessors$1(SocketServer.scala:279) at scala.collection.immutable.Range.foreach$mVc$sp(Range.scala:158) at kafka.network.SocketServer.addDataPlaneProcessors(SocketServer.scala:278) at kafka.network.SocketServer.$anonfun$createDataPlaneAcceptorsAndProcessors$1(SocketServer.scala:241) at kafka.network.SocketServer.$anonfun$createDataPlaneAcceptorsAndProcessors$1$adapted(SocketServer.scala:238) at scala.collection.mutable.ResizableArray.foreach(ResizableArray.scala:62) at scala.collection.mutable.ResizableArray.foreach$(ResizableArray.scala:55) at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:49) at kafka.network.SocketServer.createDataPlaneAcceptorsAndProcessors(SocketServer.scala:238) at kafka.network.SocketServer.startup(SocketServer.scala:121) at kafka.server.KafkaServer.startup(KafkaServer.scala:265) at kafka.server.KafkaServerStartable.startup(KafkaServerStartable.scala:44) at kafka.Kafka$.main(Kafka.scala:84) at kafka.Kafka.main(Kafka.scala)Caused by: org.apache.kafka.common.config.ConfigException: Invalid value java.lang.RuntimeException: Delegated task threw Exception/Error for configuration A client SSLEngine created with the provided settings can't connect to a server SSLEngine created with those settings. at org.apache.kafka.common.security.ssl.SslFactory.configure(SslFactory.java:100) at org.apache.kafka.common.network.SslChannelBuilder.configure(SslChannelBuilder.java:69) ... 18 more -- This message was sent by Atlassian Jira (v8.3.4#803005)
[jira] [Created] (KAFKA-10641) ACL Command hands with SSL as not existing with proper error code
Senthilnathan Muthusamy created KAFKA-10641: --- Summary: ACL Command hands with SSL as not existing with proper error code Key: KAFKA-10641 URL: https://issues.apache.org/jira/browse/KAFKA-10641 Project: Kafka Issue Type: Bug Components: core Affects Versions: 2.5.1, 2.6.0, 2.4.1, 2.5.0, 2.3.1, 2.4.0, 2.2.2, 2.2.1, 2.3.0, 2.1.1, 2.2.0, 2.1.0, 2.0.1, 2.0.0 Reporter: Senthilnathan Muthusamy Assignee: Senthilnathan Muthusamy Fix For: 2.7.0 When using ACL Command with SSL mode, the process is not terminating after successful ACL operation. -- This message was sent by Atlassian Jira (v8.3.4#803005)
RE: [EXTERNAL] Re: Enable both SASL & SSL authentication...
Hi Ron, Thanks for the details and this answers my question (i.e. we can have 2 listeners - 1 with SASL_SSL and another with SSL to achieve this). Another question related to oAuth token revoke scenario. Say once broker authenticated the presented oAuth token and if is valid for 24 hours. 1. Will broker automatically invalid the token after expiry? 2. Also if the oAuth server revoked the token (say in the 6th hour), is there a way on the broker side to invalid the token thru any configuration (something like revalidating the token in a configured internal to make sure the token still valid)? Regards, Senthil -Original Message- From: Ron Dagostino Sent: Wednesday, January 22, 2020 5:15 AM To: dev@kafka.apache.org Subject: [EXTERNAL] Re: Enable both SASL & SSL authentication... <<< some of our clients uses oAuth and some uses cert based auth Hi Senthil. Brokers support different clients using different types of authentication, so there is no problem here. The way it works is via the broker's listener -- each one listens on a separate port and is either a SSL listener (mutual cert authentication), a SASL listener (or which there are two styles, with and without encryption -- more on that below), or a PLAINTEXT listener (no authentication). One thing to clarify is that any particular client cannot authenticate with multiple identities -- Kafka does not support multiple identities on a single session -- so if the client connects on the port associated with SASL then the broker will ignore any client-side certificate. As mentioned, there are two types of listeners associated with SASL: one called SASL_PLAINTEXT where the communication happens in the clear and another called SASL_SSL where the communication is TLS-encrypted. It is this second case -- SASL_SSL -- where the client could potentially present a certificate, but the broker ignores it in this case even if the broker's config says it is required. This is done because of the constraint mentioned above -- a particular client can authenticate with at most 1 identity over any single connection. I hope this helps. You may find the blog post at https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.confluent.io%2Fblog%2Fkafka-listeners-explaineddata=02%7C01%7Csenthilm%40microsoft.com%7C0896e8bba4554c0ca32c08d79f3d1a8e%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637152957096095910sdata=WE2SeBn2c%2BAce2YgAwfjvCvsYdZS8r8sSNZewZFFEUA%3Dreserved=0 to be interesting and helpful, too. Ron On Wed, Jan 22, 2020 at 2:07 AM Senthilnathan Muthusamy wrote: > > Hi, > > We want both SASL (oAuthBearer) & SSL authentication to be enabled. However > based on the below doc, the SSL auth will be disabled if SASL is enabled. > > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdocs > .confluent.io%2Fcurrent%2Fkafka%2Fauthentication_ssl.html%23brokers > p;data=02%7C01%7Csenthilm%40microsoft.com%7C0896e8bba4554c0ca32c08d79f > 3d1a8e%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637152957096105864 > sdata=4uECZuJXY19JNS4GbzYSGeeDqMPIXE%2FTtMnSdsILX8U%3Dreserv > ed=0 > > > If any SASL authentication mechanisms are enabled for a given listener, then > SSL client authentication is disabled-even if you have specified > ssl.client.auth=required and the broker authenticates clients only using SASL > on that listener. > > How can we have both SASL & SSL authentication enabled as some of our clients > uses oAuth and some uses cert based auth? > > Appreciate any pointers. > > Thanks, > Senthil
Enable both SASL & SSL authentication...
Hi, We want both SASL (oAuthBearer) & SSL authentication to be enabled. However based on the below doc, the SSL auth will be disabled if SASL is enabled. https://docs.confluent.io/current/kafka/authentication_ssl.html#brokers If any SASL authentication mechanisms are enabled for a given listener, then SSL client authentication is disabled-even if you have specified ssl.client.auth=required and the broker authenticates clients only using SASL on that listener. How can we have both SASL & SSL authentication enabled as some of our clients uses oAuth and some uses cert based auth? Appreciate any pointers. Thanks, Senthil
RE: [EXTERNAL] Re: [DISCUSS] KIP-280: Enhanced log compaction
Hi Radai Thanks for the suggestion. This is really cool feature and specific scenario on handling the fragments... However I would strongly recommend to come up with separate KIP to discuss this scenario so that we will have a better design in place. And also not to divert the intent of the current KIP... Appreciate your valuable feedback! Regards, Senthil -Original Message- From: radai Sent: Thursday, December 12, 2019 11:40 AM To: dev@kafka.apache.org Subject: Re: [EXTERNAL] Re: [DISCUSS] KIP-280: Enhanced log compaction may I suggest that if, under "header" strategy, multiple records are found with identical header values they are ALL kept? this would be useful in cases where users send larger payloads than max record size to kafka and are forced to fragment them - by setting the same header in all fragments it would become possible to properly log-compact topics with such fragmented payloads. On Tue, Nov 26, 2019 at 10:24 PM Senthilnathan Muthusamy wrote: > > Thanks Jun for confirming! > > I have updated the KIP (added recommendation section and special case in > handling LEO record for non-offset based compaction strategy). Please review > and let me know if you have any other feedback. > > Regards, > Senthil > > -Original Message- > From: Jun Rao > Sent: Tuesday, November 26, 2019 4:36 PM > To: dev > Subject: [EXTERNAL] Re: [DISCUSS] KIP-280: Enhanced log compaction > > Hi, Senthil, > > Sorry for the delay. > > 51. It seems that we can just remove the last record from the batch, but > keeps the batch during compaction. The batch level metadata is enough to > preserve the log end offset. > > 53. Yes, your understanding is correct. So we could recommend users to set " > max.compaction.lag.ms" properly if they care about deletes. > > Could you add both to the KIP? > > Thanks, > > Jun > > > On Tue, Nov 26, 2019 at 5:09 AM Senthilnathan Muthusamy > wrote: > > > Hi Gouzhang & Jun, > > > > Can one of you please confirm/respond to the below mail so that I > > will go ahead and update the KIP and proceed. > > > > Thanks > > Senthil > > > > - Senthil > > > > From: Senthilnathan Muthusamy > > Sent: Wednesday, November 20, 2019 5:04:20 PM > > To: dev@kafka.apache.org > > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > > > > > > > Hi Gouzhang & Jun, > > > > Thanks for the detailed on the scenarios. > > > > #51 => thanks for the details Gouzhang with example. Does followers > > won't be sync'ing LEO as well with leader? If yes, keeping last > > record always (without compaction for non-offset scenarios) would > > work and this needed only if the new strategy ends up removing LEO > > record, right? Also I couldn’t able to retrieve Jason's mail related > > to creating an empty message... Can you please forward if you have? > > Wondering how that can solve this particular issue unless creating > > record for random key that won't conflict with the producer/consumer keys > > for that topic/partition. > > > > #53 => I see that this can happen for the low produce rate from > > remaining ineligible for compaction for an unbounded duration where by " > > delete.retention.ms" triggers that removes the tombstone record. If > > that's the case (please correct me if I am missing any other > > scenarios), then we can suggest the Kafka users to have "segment.ms" & " > > max.compaction.lag.ms" (as compaction won't happen on active > > segment) to be smaller than the "delete.retention.ms" and that > > should address this scenario, right? > > > > Thanks, > > Senthil > > > > -Original Message- > > From: Jun Rao > > Sent: Wednesday, November 13, 2019 9:31 AM > > To: dev > > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > > > Hi, Seth, > > > > 51. The difference is that with the offset compaction strategy, the > > message corresponding to the last offset is always the winning > > record and will never be removed. But with the new strategies, it's > > now possible that the message corresponding to the last offset is a > > losing record and needs to be removed. > > > > 53. Similarly, with the offset compaction strategy, if we see a > > non-tombstone record after a tombstone record, the non-tombstone > > record is always the winning one. However, with the new strategies, > > that non-tombstone record with a larger offset could be a losing > > record.
RE: [EXTERNAL] Re: [VOTE] KIP-280: Enhanced log compaction
Sure Guozhang! Working on it and will post it when it is ready... Thanks, Senthil -Original Message- From: Guozhang Wang Sent: Sunday, December 8, 2019 6:47 PM To: dev Subject: [EXTERNAL] Re: [VOTE] KIP-280: Enhanced log compaction Thanks for the updated KIP, recasting my vote +1 on it again. Thanks for driving the KIP discussion, and please feel free to ping the community when the PR is ready for reviews! :) One minor recommendation is to break it into smaller PRs to help on faster reviews and code merges. Guozhang On Tue, Nov 26, 2019 at 10:24 PM Senthilnathan Muthusamy wrote: > Jun, > > If the updated KIP looks good, can you please vote for it. > > Thanks, > Senthil > > -Original Message- > From: Jun Rao > Sent: Thursday, November 7, 2019 4:33 PM > To: dev > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > Hi, Senthil, > > Thanks for the KIP. Added a few more comments on the discussion thread. > > Jun > > On Wed, Nov 6, 2019 at 3:38 AM Senthilnathan Muthusamy < > senth...@microsoft.com.invalid> wrote: > > > Thanks Matthias! > > > > Received 2 +1 binding... looking for one more +1 binding ! > > > > Regards, > > Senthil > > > > -Original Message- > > From: Matthias J. Sax > > Sent: Wednesday, November 6, 2019 12:10 AM > > To: dev@kafka.apache.org > > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > > > +1 (binding) > > > > On 11/5/19 11:44 AM, Senthilnathan Muthusamy wrote: > > > Thanks Gouzhang and I have made a note in the JIRA item to update > > > the > > wiki. > > > > > > Till now got 1 +1 binding... waiting for 2 more +1 binding... thnx! > > > > > > Regards, > > > Senthil > > > > > > -Original Message- > > > From: Guozhang Wang > > > Sent: Monday, November 4, 2019 11:01 AM > > > To: dev > > > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > > > > > I only have one minor comment on the DISCUSS thread, otherwise I'm > > > +1 > > (binding). > > > > > > On Mon, Nov 4, 2019 at 9:53 AM Senthilnathan Muthusamy < > > senth...@microsoft.com.invalid> wrote: > > > > > >> Hi all, > > >> > > >> I would like to start the vote on the updated KIP-280: Enhanced > > >> log compaction. Thanks to Guozhang, Matthias & Tom for the > > >> valuable feedback on the discussion thread... > > >> > > >> KIP: > > >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2 > > >> Fc > > >> wi > > >> k > > >> i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnha > > >> nc > > >> ed > > >> % > > >> 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7C > > >> a8 > > >> ca > > >> 2 > > >> 5d3f1894d0d271f08d7615966d3%7C72f988bf86f141af91ab2d7cd011db47%7C > > >> 1% > > >> 7C > > >> 0 > > >> %7C637085005478393331sdata=qrttmbYi2Ea4qfcF5qKVbn7CaYwmvRylO > > >> 85 > > >> df > > >> j > > >> IY6pI%3Dreserved=0 > > >> > > >> JIRA: > > >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2 > > >> Fi > > >> ss > > >> u > > >> es.apache.org%2Fjira%2Fbrowse%2FKAFKA-7061data=02%7C01%7Csen > > >> th > > >> il > > >> m > > >> %40microsoft.com%7Ca8ca25d3f1894d0d271f08d7615966d3%7C72f988bf86f > > >> 14 > > >> 1a > > >> f > > >> 91ab2d7cd011db47%7C1%7C0%7C637085005478393331sdata=7c%2BzF3X > > >> RR > > >> z% > > >> 2 > > >> BijyyjBRntP6ZMWqnyzy4BEE8rqnZaF1s%3Dreserved=0 > > >> > > >> Thanks, > > >> Senthil > > >> > > > > > > > > > -- > > > -- Guozhang > > > > > > > > -- -- Guozhang
RE: [EXTERNAL] Re: [VOTE] KIP-280: Enhanced log compaction
Thanks Jun and added new recommendation for the consumer in the KIP. As we have 3 +1 building votes (Guozhang, Matthias & Jun), considering this KIP as accepted. Regards, Senthil -Original Message- From: Jun Rao Sent: Wednesday, November 27, 2019 9:16 AM To: dev Subject: [EXTERNAL] Re: [VOTE] KIP-280: Enhanced log compaction Hi, Senthil, Thanks for the updated KIP. +1 from me. Could you also add in the recommendation section what the users should do when consuming the compacted topic with the new strategies (e.g. have to be more careful with what records to keep)? Jun On Tue, Nov 26, 2019 at 10:24 PM Senthilnathan Muthusamy wrote: > Jun, > > If the updated KIP looks good, can you please vote for it. > > Thanks, > Senthil > > -Original Message- > From: Jun Rao > Sent: Thursday, November 7, 2019 4:33 PM > To: dev > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > Hi, Senthil, > > Thanks for the KIP. Added a few more comments on the discussion thread. > > Jun > > On Wed, Nov 6, 2019 at 3:38 AM Senthilnathan Muthusamy < > senth...@microsoft.com.invalid> wrote: > > > Thanks Matthias! > > > > Received 2 +1 binding... looking for one more +1 binding ! > > > > Regards, > > Senthil > > > > -Original Message- > > From: Matthias J. Sax > > Sent: Wednesday, November 6, 2019 12:10 AM > > To: dev@kafka.apache.org > > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > > > +1 (binding) > > > > On 11/5/19 11:44 AM, Senthilnathan Muthusamy wrote: > > > Thanks Gouzhang and I have made a note in the JIRA item to update > > > the > > wiki. > > > > > > Till now got 1 +1 binding... waiting for 2 more +1 binding... thnx! > > > > > > Regards, > > > Senthil > > > > > > -Original Message- > > > From: Guozhang Wang > > > Sent: Monday, November 4, 2019 11:01 AM > > > To: dev > > > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > > > > > I only have one minor comment on the DISCUSS thread, otherwise I'm > > > +1 > > (binding). > > > > > > On Mon, Nov 4, 2019 at 9:53 AM Senthilnathan Muthusamy < > > senth...@microsoft.com.invalid> wrote: > > > > > >> Hi all, > > >> > > >> I would like to start the vote on the updated KIP-280: Enhanced > > >> log compaction. Thanks to Guozhang, Matthias & Tom for the > > >> valuable feedback on the discussion thread... > > >> > > >> KIP: > > >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2 > > >> Fc > > >> wi > > >> k > > >> i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnha > > >> nc > > >> ed > > >> % > > >> 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7C > > >> a8 > > >> ca > > >> 2 > > >> 5d3f1894d0d271f08d7615966d3%7C72f988bf86f141af91ab2d7cd011db47%7C > > >> 1% > > >> 7C > > >> 0 > > >> %7C637085005478393331sdata=qrttmbYi2Ea4qfcF5qKVbn7CaYwmvRylO > > >> 85 > > >> df > > >> j > > >> IY6pI%3Dreserved=0 > > >> > > >> JIRA: > > >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2 > > >> Fi > > >> ss > > >> u > > >> es.apache.org%2Fjira%2Fbrowse%2FKAFKA-7061data=02%7C01%7Csen > > >> th > > >> il > > >> m > > >> %40microsoft.com%7Ca8ca25d3f1894d0d271f08d7615966d3%7C72f988bf86f > > >> 14 > > >> 1a > > >> f > > >> 91ab2d7cd011db47%7C1%7C0%7C637085005478393331sdata=7c%2BzF3X > > >> RR > > >> z% > > >> 2 > > >> BijyyjBRntP6ZMWqnyzy4BEE8rqnZaF1s%3Dreserved=0 > > >> > > >> Thanks, > > >> Senthil > > >> > > > > > > > > > -- > > > -- Guozhang > > > > > > > >
RE: [EXTERNAL] Re: [DISCUSS] KIP-280: Enhanced log compaction
Thanks Jun for confirming! I have updated the KIP (added recommendation section and special case in handling LEO record for non-offset based compaction strategy). Please review and let me know if you have any other feedback. Regards, Senthil -Original Message- From: Jun Rao Sent: Tuesday, November 26, 2019 4:36 PM To: dev Subject: [EXTERNAL] Re: [DISCUSS] KIP-280: Enhanced log compaction Hi, Senthil, Sorry for the delay. 51. It seems that we can just remove the last record from the batch, but keeps the batch during compaction. The batch level metadata is enough to preserve the log end offset. 53. Yes, your understanding is correct. So we could recommend users to set " max.compaction.lag.ms" properly if they care about deletes. Could you add both to the KIP? Thanks, Jun On Tue, Nov 26, 2019 at 5:09 AM Senthilnathan Muthusamy wrote: > Hi Gouzhang & Jun, > > Can one of you please confirm/respond to the below mail so that I will > go ahead and update the KIP and proceed. > > Thanks > Senthil > > - Senthil > ____ > From: Senthilnathan Muthusamy > Sent: Wednesday, November 20, 2019 5:04:20 PM > To: dev@kafka.apache.org > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > > > Hi Gouzhang & Jun, > > Thanks for the detailed on the scenarios. > > #51 => thanks for the details Gouzhang with example. Does followers > won't be sync'ing LEO as well with leader? If yes, keeping last record > always (without compaction for non-offset scenarios) would work and > this needed only if the new strategy ends up removing LEO record, > right? Also I couldn’t able to retrieve Jason's mail related to > creating an empty message... Can you please forward if you have? > Wondering how that can solve this particular issue unless creating > record for random key that won't conflict with the producer/consumer keys for > that topic/partition. > > #53 => I see that this can happen for the low produce rate from > remaining ineligible for compaction for an unbounded duration where by " > delete.retention.ms" triggers that removes the tombstone record. If > that's the case (please correct me if I am missing any other > scenarios), then we can suggest the Kafka users to have "segment.ms" & " > max.compaction.lag.ms" (as compaction won't happen on active segment) > to be smaller than the "delete.retention.ms" and that should address > this scenario, right? > > Thanks, > Senthil > > -Original Message- > From: Jun Rao > Sent: Wednesday, November 13, 2019 9:31 AM > To: dev > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > Hi, Seth, > > 51. The difference is that with the offset compaction strategy, the > message corresponding to the last offset is always the winning record > and will never be removed. But with the new strategies, it's now > possible that the message corresponding to the last offset is a losing > record and needs to be removed. > > 53. Similarly, with the offset compaction strategy, if we see a > non-tombstone record after a tombstone record, the non-tombstone > record is always the winning one. However, with the new strategies, > that non-tombstone record with a larger offset could be a losing > record. The question is then how do we retain the tombstone long > enough so that we could still recognize that the non-tombstone record should > be ignored. > > Thanks, > > Jun > > -Original Message- > From: Guozhang Wang > Sent: Tuesday, November 12, 2019 6:09 PM > To: dev > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > Hello Senthil, > > Let me try to re-iterate on Jun's comments with some context here: > > 51: today with the offset-only compaction strategy, the last record of > the log (we call it the log-end-record, whose offset is > log-end-offset) would always be preserved and not compacted. This is > kinda important for replication since followers reason about the > log-end-offset on the leader. > Consider this case: three replicas of a partition, leader 1 and > follower 2 and 3. > > Leader 1 has records a, b, c, d and d is the current last record of > the partition, the current log-end-offset is 3 (assuming record a's > offset is 0). > Follower 2 has replicated a, b, c, d. Log-end-offset is 3 Follower 3 > has replicated a, b, c but not yet replicated d. Log-end-offset is 2. > > NOTE that the compaction triggering are independent on brokers, it is > possible that leader 1 triggers compaction and deletes record d, while > other followers have not triggered compaction yet. At this moment the > leader's log becomes a, b, c. Now l
RE: [VOTE] KIP-280: Enhanced log compaction
Jun, If the updated KIP looks good, can you please vote for it. Thanks, Senthil -Original Message- From: Jun Rao Sent: Thursday, November 7, 2019 4:33 PM To: dev Subject: Re: [VOTE] KIP-280: Enhanced log compaction Hi, Senthil, Thanks for the KIP. Added a few more comments on the discussion thread. Jun On Wed, Nov 6, 2019 at 3:38 AM Senthilnathan Muthusamy wrote: > Thanks Matthias! > > Received 2 +1 binding... looking for one more +1 binding ! > > Regards, > Senthil > > -Original Message- > From: Matthias J. Sax > Sent: Wednesday, November 6, 2019 12:10 AM > To: dev@kafka.apache.org > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > +1 (binding) > > On 11/5/19 11:44 AM, Senthilnathan Muthusamy wrote: > > Thanks Gouzhang and I have made a note in the JIRA item to update > > the > wiki. > > > > Till now got 1 +1 binding... waiting for 2 more +1 binding... thnx! > > > > Regards, > > Senthil > > > > -Original Message- > > From: Guozhang Wang > > Sent: Monday, November 4, 2019 11:01 AM > > To: dev > > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > > > I only have one minor comment on the DISCUSS thread, otherwise I'm > > +1 > (binding). > > > > On Mon, Nov 4, 2019 at 9:53 AM Senthilnathan Muthusamy < > senth...@microsoft.com.invalid> wrote: > > > >> Hi all, > >> > >> I would like to start the vote on the updated KIP-280: Enhanced log > >> compaction. Thanks to Guozhang, Matthias & Tom for the valuable > >> feedback on the discussion thread... > >> > >> KIP: > >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fc > >> wi > >> k > >> i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnhanc > >> ed > >> % > >> 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7Ca8 > >> ca > >> 2 > >> 5d3f1894d0d271f08d7615966d3%7C72f988bf86f141af91ab2d7cd011db47%7C1% > >> 7C > >> 0 > >> %7C637085005478393331sdata=qrttmbYi2Ea4qfcF5qKVbn7CaYwmvRylO85 > >> df > >> j > >> IY6pI%3Dreserved=0 > >> > >> JIRA: > >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fi > >> ss > >> u > >> es.apache.org%2Fjira%2Fbrowse%2FKAFKA-7061data=02%7C01%7Csenth > >> il > >> m > >> %40microsoft.com%7Ca8ca25d3f1894d0d271f08d7615966d3%7C72f988bf86f14 > >> 1a > >> f > >> 91ab2d7cd011db47%7C1%7C0%7C637085005478393331sdata=7c%2BzF3XRR > >> z% > >> 2 > >> BijyyjBRntP6ZMWqnyzy4BEE8rqnZaF1s%3Dreserved=0 > >> > >> Thanks, > >> Senthil > >> > > > > > > -- > > -- Guozhang > > > >
Re: [DISCUSS] KIP-280: Enhanced log compaction
Hi Gouzhang & Jun, Can one of you please confirm/respond to the below mail so that I will go ahead and update the KIP and proceed. Thanks Senthil - Senthil From: Senthilnathan Muthusamy Sent: Wednesday, November 20, 2019 5:04:20 PM To: dev@kafka.apache.org Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction Hi Gouzhang & Jun, Thanks for the detailed on the scenarios. #51 => thanks for the details Gouzhang with example. Does followers won't be sync'ing LEO as well with leader? If yes, keeping last record always (without compaction for non-offset scenarios) would work and this needed only if the new strategy ends up removing LEO record, right? Also I couldn’t able to retrieve Jason's mail related to creating an empty message... Can you please forward if you have? Wondering how that can solve this particular issue unless creating record for random key that won't conflict with the producer/consumer keys for that topic/partition. #53 => I see that this can happen for the low produce rate from remaining ineligible for compaction for an unbounded duration where by "delete.retention.ms" triggers that removes the tombstone record. If that's the case (please correct me if I am missing any other scenarios), then we can suggest the Kafka users to have "segment.ms" & "max.compaction.lag.ms" (as compaction won't happen on active segment) to be smaller than the "delete.retention.ms" and that should address this scenario, right? Thanks, Senthil -Original Message- From: Jun Rao Sent: Wednesday, November 13, 2019 9:31 AM To: dev Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Hi, Seth, 51. The difference is that with the offset compaction strategy, the message corresponding to the last offset is always the winning record and will never be removed. But with the new strategies, it's now possible that the message corresponding to the last offset is a losing record and needs to be removed. 53. Similarly, with the offset compaction strategy, if we see a non-tombstone record after a tombstone record, the non-tombstone record is always the winning one. However, with the new strategies, that non-tombstone record with a larger offset could be a losing record. The question is then how do we retain the tombstone long enough so that we could still recognize that the non-tombstone record should be ignored. Thanks, Jun -Original Message- From: Guozhang Wang Sent: Tuesday, November 12, 2019 6:09 PM To: dev Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Hello Senthil, Let me try to re-iterate on Jun's comments with some context here: 51: today with the offset-only compaction strategy, the last record of the log (we call it the log-end-record, whose offset is log-end-offset) would always be preserved and not compacted. This is kinda important for replication since followers reason about the log-end-offset on the leader. Consider this case: three replicas of a partition, leader 1 and follower 2 and 3. Leader 1 has records a, b, c, d and d is the current last record of the partition, the current log-end-offset is 3 (assuming record a's offset is 0). Follower 2 has replicated a, b, c, d. Log-end-offset is 3 Follower 3 has replicated a, b, c but not yet replicated d. Log-end-offset is 2. NOTE that the compaction triggering are independent on brokers, it is possible that leader 1 triggers compaction and deletes record d, while other followers have not triggered compaction yet. At this moment the leader's log becomes a, b, c. Now let's say follower 3 fetch from leader after the compaction, it will no longer see record d. Now suppose there's a leader migration and follower 3 becomes the new leader, it would accept new appends (say, it's e), and record e would be appended at *offset 3 *on new leader 3's log. But follower 2's offset 3's record is d still. Later let's say follower 2 also triggers compaction and also fetches the new record e from new leader 3: Follower 2's log would be* a(0), b(1), c(2), e(4)* where the numbers in brackets are offset number; while leader 3's log would be *a(0), b(1), c(2), e(3)*. Now you see the two logs diverges in offsets, although their log entries are the same. - One way to resolve this, is to simply never remove the last message during compaction. Another way (suggested by Jason in the old VOTE thread) is to create an empty message batch to "take up" that offset slot. 53: Again here's some context on when we can delete a tombstone (null): during compaction, if we see the latest record for a certain key is a tombstone we can remove all old records BUT that tombstone itself cannot be removed immediately since the old records may already be fetched by some consumers and that tombstone may not be fetched by consumer yet. Also that tombstone may have not been repli
RE: [DISCUSS] KIP-280: Enhanced log compaction
kerconfigsdata=02%7C01%7Csenthilm%40microsoft.com%7C9e3a2484adc54d48122408d767de70ab%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637092077377837652sdata=TiIBt9QNxk9UWkLhrbJ0t1vTOhbxMDMc2DaNGqLWqdA%3Dreserved=0 Now consider under timestamp / header based compaction strategy: a later record may still be deprecated by an early tombstone, so if that tombstone is already removed then the log compaction thread would not remove that later record and hence the logic would be broken. That's why we also need consider "delaying" the removal of the tombstone in this case. Personally I think we can still piggy-back on the "delete.retention.ms" since its default value is 8640ms == 1 day, and we just need to document that if you have timestamp / header based compaction, then it's YOUR responsibility as the Kafka user to make sure that the timestamp / header out of ordering is smaller than the value of "delete.retention.ms". Otherwise some later records with smaller timestamp / headers may not be compacted correctly since the tombstone is already gone and hence we do not have the "proof" to remove it anymore. Does that make sense to you? Guozhang On Tue, Nov 12, 2019 at 9:15 AM Senthilnathan Muthusamy wrote: > Hi Jun, > > Thanks for the response and please find below the response! > > #50 - got it... > > #51 - not sure how the last record will be deleted bcoz of this new > compact strategy. The reason I am asking is, the compaction is based > out of offsetmap and the new strategy logic is purely within the > offsetmap... the offsetmap will always keep track of the latest offset > irrespective of the compaction strategy. You can have a look at the PR > of the new compaction strategy changes: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgith > ub.com%2Fapache%2Fkafka%2Fpull%2F7528%2Ffilesdata=02%7C01%7Csenth > ilm%40microsoft.com%7C9e3a2484adc54d48122408d767de70ab%7C72f988bf86f14 > 1af91ab2d7cd011db47%7C1%7C0%7C637092077377837652sdata=j%2FxNbJloj > YXIk8KdEe%2FIUrmy0iX6BPoNWUMM9rdjvd4%3Dreserved=0 > > #52 - sure, I have updated JIRA to include this details in the wiki. > > #53 - as I am pointed out in #51, the tombstone is abstract to this > change (i.e. the tombstone is handled within LogCleaner and the > compact strategy is by the offsetmap). this is what my understand on > the tombstone based on the code walk-thru... please let me know if I am > missing anything here... > > Thanks, > Senthil > > -Original Message- > From: Jun Rao > Sent: Thursday, November 7, 2019 4:32 PM > To: dev > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > Hi, Senthil, > > Thanks for bringing back this KIP. Overall, this seems like a useful > feature. A few comments below. > > 50. One use case for the timestamp based compaction is to resolve > conflicts during data center failures. The failover of a data center > typically happens much longer tha millisec. So, timestamp could be > enough to determine the value to keep. > > 51. With the timestamp/header strategy, it seems that it may now be > possible that the last record could be removed during compaction. For > example, if the active segment is empty, the last record in the > previous segment could be removed due to compaction. A new replica > then won't see the true end offset of the partition. If that replica > ever becomes the leader, it could write a different record on the same > end offset, which will be weird. > > 52. With the timestamp/header strategy, the behavior of the > application may need to change. In particular, the application can't > just blindly take the record with a larger offset and assuming that it's the > value to keep. > It needs to check the timestamp or the header now. So, it would be > useful to at least document this. > > 53. This also adds complexity for deletes. Currently, we use a null > payload to indicate a delete tombstone. The tombstone can be removed > once all previous records with the same key have been removed. If the > new strategies apply to tombstones, it's not clear when a tombstone > can be removed since subsequent records could have > timestamp/sequenceId smaller than that in the tombstone. It would be > useful to think this through and document the expected behavior. > > Jun > > On Tue, Nov 5, 2019 at 11:37 AM Senthilnathan Muthusamy < > senth...@microsoft.com.invalid> wrote: > > > Hi Guozhang, > > > > Sure and I have made a note in the JIRA item to make sure the wiki > > is updated. > > > > Thanks, > > Senthil > > > > -Original Message- > > From: Guozhang Wang > > Sent: Monday, November 4, 2019 11:00 AM &g
RE: [DISCUSS] KIP-280: Enhanced log compaction
Hi Jun, Thanks for the response and please find below the response! #50 - got it... #51 - not sure how the last record will be deleted bcoz of this new compact strategy. The reason I am asking is, the compaction is based out of offsetmap and the new strategy logic is purely within the offsetmap... the offsetmap will always keep track of the latest offset irrespective of the compaction strategy. You can have a look at the PR of the new compaction strategy changes: https://github.com/apache/kafka/pull/7528/files #52 - sure, I have updated JIRA to include this details in the wiki. #53 - as I am pointed out in #51, the tombstone is abstract to this change (i.e. the tombstone is handled within LogCleaner and the compact strategy is by the offsetmap). this is what my understand on the tombstone based on the code walk-thru... please let me know if I am missing anything here... Thanks, Senthil -Original Message- From: Jun Rao Sent: Thursday, November 7, 2019 4:32 PM To: dev Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Hi, Senthil, Thanks for bringing back this KIP. Overall, this seems like a useful feature. A few comments below. 50. One use case for the timestamp based compaction is to resolve conflicts during data center failures. The failover of a data center typically happens much longer tha millisec. So, timestamp could be enough to determine the value to keep. 51. With the timestamp/header strategy, it seems that it may now be possible that the last record could be removed during compaction. For example, if the active segment is empty, the last record in the previous segment could be removed due to compaction. A new replica then won't see the true end offset of the partition. If that replica ever becomes the leader, it could write a different record on the same end offset, which will be weird. 52. With the timestamp/header strategy, the behavior of the application may need to change. In particular, the application can't just blindly take the record with a larger offset and assuming that it's the value to keep. It needs to check the timestamp or the header now. So, it would be useful to at least document this. 53. This also adds complexity for deletes. Currently, we use a null payload to indicate a delete tombstone. The tombstone can be removed once all previous records with the same key have been removed. If the new strategies apply to tombstones, it's not clear when a tombstone can be removed since subsequent records could have timestamp/sequenceId smaller than that in the tombstone. It would be useful to think this through and document the expected behavior. Jun On Tue, Nov 5, 2019 at 11:37 AM Senthilnathan Muthusamy wrote: > Hi Guozhang, > > Sure and I have made a note in the JIRA item to make sure the wiki is > updated. > > Thanks, > Senthil > > -Original Message- > From: Guozhang Wang > Sent: Monday, November 4, 2019 11:00 AM > To: dev > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > Hello Senthilnathan, > > Thanks for revamping on the KIP. I have only one comment about the > wiki otherwise LGTM. > > 1. We should emphasize that the newly introduced config yields to the > existing "log.cleanup.policy", i.e. if the latter's value is `delete` > not `compact`, then the previous config would be ignored. > > > Guozhang > > On Mon, Nov 4, 2019 at 9:52 AM Senthilnathan Muthusamy < > senth...@microsoft.com.invalid> wrote: > > > Hi all, > > > > I will start the vote thread shortly for this updated KIP. If there > > are any more thoughts I would love to hear them. > > > > Thanks, > > Senthil > > > > -Original Message- > > From: Senthilnathan Muthusamy > > Sent: Thursday, October 31, 2019 3:51 AM > > To: dev@kafka.apache.org > > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > > > Hi Matthias > > > > Thanks for the response. > > > > (1) Yes > > > > (2) Yes, and the config name will be the same (i.e. > > `log.cleaner.compaction.strategy` & > > `log.cleaner.compaction.strategy.header`) at broker level and topic > > level (to override broker level default compact strategy). Please > > let me know if we need to keep it in different naming convention. Note: > > Broker level (which will be in the server.properties) configuration > > is optional and default it to offset. Topic level configuration will > > be default to broker level config... > > > > (3) By this new way, it avoids another config parameter and also in > > feature if any new strategy like header need addition info, no > > additional config required. As this got discussed already and agreed > > to have separate config, I will revert it.
RE: [VOTE] KIP-280: Enhanced log compaction
Thanks Matthias! Received 2 +1 binding... looking for one more +1 binding ! Regards, Senthil -Original Message- From: Matthias J. Sax Sent: Wednesday, November 6, 2019 12:10 AM To: dev@kafka.apache.org Subject: Re: [VOTE] KIP-280: Enhanced log compaction +1 (binding) On 11/5/19 11:44 AM, Senthilnathan Muthusamy wrote: > Thanks Gouzhang and I have made a note in the JIRA item to update the wiki. > > Till now got 1 +1 binding... waiting for 2 more +1 binding... thnx! > > Regards, > Senthil > > -Original Message- > From: Guozhang Wang > Sent: Monday, November 4, 2019 11:01 AM > To: dev > Subject: Re: [VOTE] KIP-280: Enhanced log compaction > > I only have one minor comment on the DISCUSS thread, otherwise I'm +1 > (binding). > > On Mon, Nov 4, 2019 at 9:53 AM Senthilnathan Muthusamy > wrote: > >> Hi all, >> >> I would like to start the vote on the updated KIP-280: Enhanced log >> compaction. Thanks to Guozhang, Matthias & Tom for the valuable >> feedback on the discussion thread... >> >> KIP: >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcwi >> k >> i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnhanced >> % >> 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7Ca8ca >> 2 >> 5d3f1894d0d271f08d7615966d3%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C >> 0 >> %7C637085005478393331sdata=qrttmbYi2Ea4qfcF5qKVbn7CaYwmvRylO85df >> j >> IY6pI%3Dreserved=0 >> >> JIRA: >> https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fiss >> u >> es.apache.org%2Fjira%2Fbrowse%2FKAFKA-7061data=02%7C01%7Csenthil >> m >> %40microsoft.com%7Ca8ca25d3f1894d0d271f08d7615966d3%7C72f988bf86f141a >> f >> 91ab2d7cd011db47%7C1%7C0%7C637085005478393331sdata=7c%2BzF3XRRz% >> 2 >> BijyyjBRntP6ZMWqnyzy4BEE8rqnZaF1s%3Dreserved=0 >> >> Thanks, >> Senthil >> > > > -- > -- Guozhang >
RE: [VOTE] KIP-280: Enhanced log compaction
Thanks Gouzhang and I have made a note in the JIRA item to update the wiki. Till now got 1 +1 binding... waiting for 2 more +1 binding... thnx! Regards, Senthil -Original Message- From: Guozhang Wang Sent: Monday, November 4, 2019 11:01 AM To: dev Subject: Re: [VOTE] KIP-280: Enhanced log compaction I only have one minor comment on the DISCUSS thread, otherwise I'm +1 (binding). On Mon, Nov 4, 2019 at 9:53 AM Senthilnathan Muthusamy wrote: > Hi all, > > I would like to start the vote on the updated KIP-280: Enhanced log > compaction. Thanks to Guozhang, Matthias & Tom for the valuable > feedback on the discussion thread... > > KIP: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcwik > i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnhanced% > 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7Ca8ca2 > 5d3f1894d0d271f08d7615966d3%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0 > %7C637085005478393331sdata=qrttmbYi2Ea4qfcF5qKVbn7CaYwmvRylO85dfj > IY6pI%3Dreserved=0 > > JIRA: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fissu > es.apache.org%2Fjira%2Fbrowse%2FKAFKA-7061data=02%7C01%7Csenthilm > %40microsoft.com%7Ca8ca25d3f1894d0d271f08d7615966d3%7C72f988bf86f141af > 91ab2d7cd011db47%7C1%7C0%7C637085005478393331sdata=7c%2BzF3XRRz%2 > BijyyjBRntP6ZMWqnyzy4BEE8rqnZaF1s%3Dreserved=0 > > Thanks, > Senthil > -- -- Guozhang
RE: [DISCUSS] KIP-280: Enhanced log compaction
Hi Guozhang, Sure and I have made a note in the JIRA item to make sure the wiki is updated. Thanks, Senthil -Original Message- From: Guozhang Wang Sent: Monday, November 4, 2019 11:00 AM To: dev Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Hello Senthilnathan, Thanks for revamping on the KIP. I have only one comment about the wiki otherwise LGTM. 1. We should emphasize that the newly introduced config yields to the existing "log.cleanup.policy", i.e. if the latter's value is `delete` not `compact`, then the previous config would be ignored. Guozhang On Mon, Nov 4, 2019 at 9:52 AM Senthilnathan Muthusamy wrote: > Hi all, > > I will start the vote thread shortly for this updated KIP. If there > are any more thoughts I would love to hear them. > > Thanks, > Senthil > > -Original Message- > From: Senthilnathan Muthusamy > Sent: Thursday, October 31, 2019 3:51 AM > To: dev@kafka.apache.org > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > Hi Matthias > > Thanks for the response. > > (1) Yes > > (2) Yes, and the config name will be the same (i.e. > `log.cleaner.compaction.strategy` & > `log.cleaner.compaction.strategy.header`) at broker level and topic > level (to override broker level default compact strategy). Please let > me know if we need to keep it in different naming convention. Note: > Broker level (which will be in the server.properties) configuration is > optional and default it to offset. Topic level configuration will be > default to broker level config... > > (3) By this new way, it avoids another config parameter and also in > feature if any new strategy like header need addition info, no > additional config required. As this got discussed already and agreed > to have separate config, I will revert it. KIP updated... > > (4) Done > > (5) Updated > > (6) Updated to pick the first header in the list > > Please let me know if you have any other questions. > > Thanks, > Senthil > > -Original Message- > From: Matthias J. Sax > Sent: Thursday, October 31, 2019 12:13 AM > To: dev@kafka.apache.org > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > Thanks for picking up this KIP, Senthil. > > (1) As far as I remember, the main issue of the original proposal was > a missing topic level configuration for the compaction strategy. With > this being addressed, I am in favor of this KIP. > > (2) With regard to (1), it seems we would need a new topic level > config `compaction.strategy`, and `log.cleaner.compaction.strategy` > would be the default strategy (ie, broker level config) if a topic does not > overwrite it? > > (3) Why did you remove `log.cleaner.compaction.strategy.header` > parameter and change the accepted values of > `log.cleaner.compaction.strategy` to "header." instead of keeping > "header"? The original approach seems to be cleaner, and I think this > was discussed on the original discuss thread already. > > (4) Nit: For the "timestamp" compaction strategy you changed the KIP > to > > -> `The record [create] timestamp` > > This is miss leading IMHO, because it depends on the broker/log > configuration `(log.)message.timestamp.type` that can either be > `CreateTime` or `LogAppendTime` what the actual record timestamp is. I > would just remove "create" to keep it unspecified. > > (5) Nit: the section "Public Interfaces" should list the newly > introduced configs -- configuration parameters are a public interface. > > (6) What do you mean by "first level header lookup"? The term "first > level" indicates some hierarchy, but headers don't have any hierarchy > -- it's just a list of key-value pairs? If you mean the _order_ of the > headers, ie, pick the first header in the list that matches the key, > please rephrase it to make it clearer. > > > > @Tom: I agree with all you are saying, however, I still think that > this KIP will improve the overall situation, because everything you > pointed out is actually true with offset based compaction, too. > > The KIP is not a silver bullet that solves all issue for interleaved > writes, but I personally believe, it's a good improvement. > > > > -Matthias > > > On 10/30/19 9:45 AM, Senthilnathan Muthusamy wrote: > > Hi, > > > > Please let me know if anyone has any questions on this updated KIP-280... > > > > Thanks, > > > > Senthil > > > > -Original Message- > > From: Senthilnathan Muthusamy > > Sent: Monday, October 28, 2019 11:36 PM > > To: dev@kafka.apache.org > > Subject: RE
RE: [DISCUSS] KIP-280: Enhanced log compaction
Thanks for pointing it out Eric. Updated the KIP... Regards, Senthil -Original Message- From: Guozhang Wang Sent: Monday, November 4, 2019 11:52 AM To: dev Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Eric, I think that's a good point, in `Headers.java` we also designed the API to only have `Header lastHeader(String key);`. I think picking the last header for that key would makes more sense since internally it is organized as a list such that newer headers could consider "overwriting" the older headers. Guozhang On Mon, Nov 4, 2019 at 11:31 AM Eric Azama wrote: > Hi Senthilnathan, > > Regarding Matthias's point 6, what is the reasoning for choosing the > first occurrence of the configured header? I believe this corresponds > to the oldest value for given key. If there are multiple values for a > key, it seems more intuitive that the newest value is the one that > should be used for compaction. > > Thanks, > Eric > > On Mon, Nov 4, 2019 at 11:00 AM Guozhang Wang wrote: > > > Hello Senthilnathan, > > > > Thanks for revamping on the KIP. I have only one comment about the > > wiki otherwise LGTM. > > > > 1. We should emphasize that the newly introduced config yields to > > the existing "log.cleanup.policy", i.e. if the latter's value is > > `delete` not `compact`, then the previous config would be ignored. > > > > > > Guozhang > > > > On Mon, Nov 4, 2019 at 9:52 AM Senthilnathan Muthusamy > > wrote: > > > > > Hi all, > > > > > > I will start the vote thread shortly for this updated KIP. If > > > there are any more thoughts I would love to hear them. > > > > > > Thanks, > > > Senthil > > > > > > -Original Message- > > > From: Senthilnathan Muthusamy > > > Sent: Thursday, October 31, 2019 3:51 AM > > > To: dev@kafka.apache.org > > > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > > > > > Hi Matthias > > > > > > Thanks for the response. > > > > > > (1) Yes > > > > > > (2) Yes, and the config name will be the same (i.e. > > > `log.cleaner.compaction.strategy` & > > > `log.cleaner.compaction.strategy.header`) at broker level and > > > topic > level > > > (to override broker level default compact strategy). Please let me > > > know > > if > > > we need to keep it in different naming convention. Note: Broker > > > level (which will be in the server.properties) configuration is > > > optional and default it to offset. Topic level configuration will > > > be default to > broker > > > level config... > > > > > > (3) By this new way, it avoids another config parameter and also > > > in feature if any new strategy like header need addition info, no > additional > > > config required. As this got discussed already and agreed to have > > separate > > > config, I will revert it. KIP updated... > > > > > > (4) Done > > > > > > (5) Updated > > > > > > (6) Updated to pick the first header in the list > > > > > > Please let me know if you have any other questions. > > > > > > Thanks, > > > Senthil > > > > > > -Original Message- > > > From: Matthias J. Sax > > > Sent: Thursday, October 31, 2019 12:13 AM > > > To: dev@kafka.apache.org > > > Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction > > > > > > Thanks for picking up this KIP, Senthil. > > > > > > (1) As far as I remember, the main issue of the original proposal > > > was a missing topic level configuration for the compaction > > > strategy. With > this > > > being addressed, I am in favor of this KIP. > > > > > > (2) With regard to (1), it seems we would need a new topic level > > > config `compaction.strategy`, and > > > `log.cleaner.compaction.strategy` would be > the > > > default strategy (ie, broker level config) if a topic does not > overwrite > > it? > > > > > > (3) Why did you remove `log.cleaner.compaction.strategy.header` > > > parameter and change the accepted values of > > > `log.cleaner.compaction.strategy` to "header." instead of > > > keeping "header"? The original approach seems to be cleaner, and I > > > think this > was > > > discussed on the original discuss thread already. > > > > > > (4) Nit: F
[VOTE] KIP-280: Enhanced log compaction
Hi all, I would like to start the vote on the updated KIP-280: Enhanced log compaction. Thanks to Guozhang, Matthias & Tom for the valuable feedback on the discussion thread... KIP: https://cwiki.apache.org/confluence/display/KAFKA/KIP-280%3A+Enhanced+log+compaction JIRA: https://issues.apache.org/jira/browse/KAFKA-7061 Thanks, Senthil
RE: [DISCUSS] KIP-280: Enhanced log compaction
Hi all, I will start the vote thread shortly for this updated KIP. If there are any more thoughts I would love to hear them. Thanks, Senthil -Original Message- From: Senthilnathan Muthusamy Sent: Thursday, October 31, 2019 3:51 AM To: dev@kafka.apache.org Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction Hi Matthias Thanks for the response. (1) Yes (2) Yes, and the config name will be the same (i.e. `log.cleaner.compaction.strategy` & `log.cleaner.compaction.strategy.header`) at broker level and topic level (to override broker level default compact strategy). Please let me know if we need to keep it in different naming convention. Note: Broker level (which will be in the server.properties) configuration is optional and default it to offset. Topic level configuration will be default to broker level config... (3) By this new way, it avoids another config parameter and also in feature if any new strategy like header need addition info, no additional config required. As this got discussed already and agreed to have separate config, I will revert it. KIP updated... (4) Done (5) Updated (6) Updated to pick the first header in the list Please let me know if you have any other questions. Thanks, Senthil -Original Message- From: Matthias J. Sax Sent: Thursday, October 31, 2019 12:13 AM To: dev@kafka.apache.org Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Thanks for picking up this KIP, Senthil. (1) As far as I remember, the main issue of the original proposal was a missing topic level configuration for the compaction strategy. With this being addressed, I am in favor of this KIP. (2) With regard to (1), it seems we would need a new topic level config `compaction.strategy`, and `log.cleaner.compaction.strategy` would be the default strategy (ie, broker level config) if a topic does not overwrite it? (3) Why did you remove `log.cleaner.compaction.strategy.header` parameter and change the accepted values of `log.cleaner.compaction.strategy` to "header." instead of keeping "header"? The original approach seems to be cleaner, and I think this was discussed on the original discuss thread already. (4) Nit: For the "timestamp" compaction strategy you changed the KIP to -> `The record [create] timestamp` This is miss leading IMHO, because it depends on the broker/log configuration `(log.)message.timestamp.type` that can either be `CreateTime` or `LogAppendTime` what the actual record timestamp is. I would just remove "create" to keep it unspecified. (5) Nit: the section "Public Interfaces" should list the newly introduced configs -- configuration parameters are a public interface. (6) What do you mean by "first level header lookup"? The term "first level" indicates some hierarchy, but headers don't have any hierarchy -- it's just a list of key-value pairs? If you mean the _order_ of the headers, ie, pick the first header in the list that matches the key, please rephrase it to make it clearer. @Tom: I agree with all you are saying, however, I still think that this KIP will improve the overall situation, because everything you pointed out is actually true with offset based compaction, too. The KIP is not a silver bullet that solves all issue for interleaved writes, but I personally believe, it's a good improvement. -Matthias On 10/30/19 9:45 AM, Senthilnathan Muthusamy wrote: > Hi, > > Please let me know if anyone has any questions on this updated KIP-280... > > Thanks, > > Senthil > > -Original Message- > From: Senthilnathan Muthusamy > Sent: Monday, October 28, 2019 11:36 PM > To: dev@kafka.apache.org > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > Hi Tom, > > Sorry for the delayed response. > > Regarding the fall back to offset decision for both timestamp & header value > is based on the previous author discuss > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.apache.org%2Fthread.html%2Ff44317eb6cd34f91966654c80509d4a457dbbccdd02b86645782be67%40%253Cdev.kafka.apache.org%253Edata=02%7C01%7Csenthilm%40microsoft.com%7Cb5c596140be1436e9fb708d75df04714%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637081159484181661sdata=%2Fap4F2CdPQe02wNDGkzjzIrxOQRTa2KraQE75dpjTzE%3Dreserved=0 > and as per the discussion, it is really required to avoid duplicates. > > And the timestamp strategy is from the original KIP author and we are keeping > it as is. > > Finally on the sequence order guarantee by the producer, it is not feasible > on waiting for ack in async / multi-threads/processes scenarios and hence the > header sequence based compact strategy with producer's responsibility to have > a unique sequence generation for the topic-partition-key level. > > Hoping this clarifies all your questions. Pl
RE: [DISCUSS] KIP-280: Enhanced log compaction
Hi Matthias Thanks for the response. (1) Yes (2) Yes, and the config name will be the same (i.e. `log.cleaner.compaction.strategy` & `log.cleaner.compaction.strategy.header`) at broker level and topic level (to override broker level default compact strategy). Please let me know if we need to keep it in different naming convention. Note: Broker level (which will be in the server.properties) configuration is optional and default it to offset. Topic level configuration will be default to broker level config... (3) By this new way, it avoids another config parameter and also in feature if any new strategy like header need addition info, no additional config required. As this got discussed already and agreed to have separate config, I will revert it. KIP updated... (4) Done (5) Updated (6) Updated to pick the first header in the list Please let me know if you have any other questions. Thanks, Senthil -Original Message- From: Matthias J. Sax Sent: Thursday, October 31, 2019 12:13 AM To: dev@kafka.apache.org Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Thanks for picking up this KIP, Senthil. (1) As far as I remember, the main issue of the original proposal was a missing topic level configuration for the compaction strategy. With this being addressed, I am in favor of this KIP. (2) With regard to (1), it seems we would need a new topic level config `compaction.strategy`, and `log.cleaner.compaction.strategy` would be the default strategy (ie, broker level config) if a topic does not overwrite it? (3) Why did you remove `log.cleaner.compaction.strategy.header` parameter and change the accepted values of `log.cleaner.compaction.strategy` to "header." instead of keeping "header"? The original approach seems to be cleaner, and I think this was discussed on the original discuss thread already. (4) Nit: For the "timestamp" compaction strategy you changed the KIP to -> `The record [create] timestamp` This is miss leading IMHO, because it depends on the broker/log configuration `(log.)message.timestamp.type` that can either be `CreateTime` or `LogAppendTime` what the actual record timestamp is. I would just remove "create" to keep it unspecified. (5) Nit: the section "Public Interfaces" should list the newly introduced configs -- configuration parameters are a public interface. (6) What do you mean by "first level header lookup"? The term "first level" indicates some hierarchy, but headers don't have any hierarchy -- it's just a list of key-value pairs? If you mean the _order_ of the headers, ie, pick the first header in the list that matches the key, please rephrase it to make it clearer. @Tom: I agree with all you are saying, however, I still think that this KIP will improve the overall situation, because everything you pointed out is actually true with offset based compaction, too. The KIP is not a silver bullet that solves all issue for interleaved writes, but I personally believe, it's a good improvement. -Matthias On 10/30/19 9:45 AM, Senthilnathan Muthusamy wrote: > Hi, > > Please let me know if anyone has any questions on this updated KIP-280... > > Thanks, > > Senthil > > -Original Message- > From: Senthilnathan Muthusamy > Sent: Monday, October 28, 2019 11:36 PM > To: dev@kafka.apache.org > Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction > > Hi Tom, > > Sorry for the delayed response. > > Regarding the fall back to offset decision for both timestamp & header value > is based on the previous author discuss > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.apache.org%2Fthread.html%2Ff44317eb6cd34f91966654c80509d4a457dbbccdd02b86645782be67%40%253Cdev.kafka.apache.org%253Edata=02%7C01%7Csenthilm%40microsoft.com%7Cfce3eed73837437b5d6b08d75c3a4692%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637079277707943399sdata=pTrTHHOD5KCtLM2YXSMWmPBMx%2BI9L5PeEe5QEcwzkKA%3Dreserved=0 > and as per the discussion, it is really required to avoid duplicates. > > And the timestamp strategy is from the original KIP author and we are keeping > it as is. > > Finally on the sequence order guarantee by the producer, it is not feasible > on waiting for ack in async / multi-threads/processes scenarios and hence the > header sequence based compact strategy with producer's responsibility to have > a unique sequence generation for the topic-partition-key level. > > Hoping this clarifies all your questions. Please let us know if you have any > further questions. > > @Guozhang Wang / @Matthias J. Sax, I see you both had a detail discussion on > the original KIP with previous author and it would great to hear your inputs > as well. > > Thanks, > Senthil > > -Original Message- > From: Tom
RE: [DISCUSS] KIP-280: Enhanced log compaction
Hi, Please let me know if anyone has any questions on this updated KIP-280... Thanks, Senthil -Original Message- From: Senthilnathan Muthusamy Sent: Monday, October 28, 2019 11:36 PM To: dev@kafka.apache.org Subject: RE: [DISCUSS] KIP-280: Enhanced log compaction Hi Tom, Sorry for the delayed response. Regarding the fall back to offset decision for both timestamp & header value is based on the previous author discuss https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.apache.org%2Fthread.html%2Ff44317eb6cd34f91966654c80509d4a457dbbccdd02b86645782be67%40%253Cdev.kafka.apache.org%253Edata=02%7C01%7Csenthilm%40microsoft.com%7Cfce3eed73837437b5d6b08d75c3a4692%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637079277707943399sdata=pTrTHHOD5KCtLM2YXSMWmPBMx%2BI9L5PeEe5QEcwzkKA%3Dreserved=0 and as per the discussion, it is really required to avoid duplicates. And the timestamp strategy is from the original KIP author and we are keeping it as is. Finally on the sequence order guarantee by the producer, it is not feasible on waiting for ack in async / multi-threads/processes scenarios and hence the header sequence based compact strategy with producer's responsibility to have a unique sequence generation for the topic-partition-key level. Hoping this clarifies all your questions. Please let us know if you have any further questions. @Guozhang Wang / @Matthias J. Sax, I see you both had a detail discussion on the original KIP with previous author and it would great to hear your inputs as well. Thanks, Senthil -Original Message- From: Tom Bentley Sent: Tuesday, October 22, 2019 2:32 AM To: dev@kafka.apache.org Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Hi Senthilnathan, In the motivation isn't it a little misleading to say "On the producer side, we clearly preserve an order for the two messages, "? IMHO, the semantics of the producer are clear that having an V2>observed order of sending records from different producers is not sufficient to guarantee ordering on the broker. You really need to send the 2nd record only after the 1st record is acked. It's the difficultly of achieving that in practice that's the true motivation for your KIP. I can see the attraction of using timestamps, but it would be helpful to explain how that really solves the problem. When the producers are in different processes on different machines you're relying on their clocks being synchronized, which is a whole subject in itself. Even if they're synchronized the resolution of System.currentTimeMillis() is typically many milliseconds. If your producers are in different threads of the same process that could be a real problem because it makes ties quite likely. And you don't explain why it's OK to resolve ties using the offset. The basis of your argument is that the offset is giving you the wrong answer. So it seems to me that using it as a tiebreaker is just narrowing the chances of getting the wrong answer. Maybe none of this matters for your use case, but I think it should be spelled out in the KIP, because it surely would matter for similar use cases. Using a sequence at least removes the problem of ties, but the interesting bit is now in how you deal with races between threads/processes in getting a sequence number allocated (which is out of scope of the KIP, I guess). How is resolving that race any simpler that resolving the motivating race by waiting for the ack of the first record sent? Kind regards, Tom On Mon, Oct 21, 2019 at 9:06 PM Senthilnathan Muthusamy wrote: > Hi All, > > We are bring back the KIP-280 to live with small correct for the > discussion & voting. Thanks to previous author Luis Cabral on the > KIP-280 initiation and we are taking over to complete and get it into 2.4... > > Below is the correction that we made to the existing KIP-280: > > * Allowing the compact strategy configuration at the topic level as > the log compaction is at the topic level and a broker can have > multiple topics. This allows the flexibility to have the strategy at > both broker level (i.e. for all topics within the broker) and topic > level (i.e. for a subset of topics within a broker) as well... > > KIP-280: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcwik > i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnhanced% > 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7C686c3 > 2fa4a554d61ae1408d756d409f6%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0 > %7C637073341017520406sdata=KrRem2KWCBscHX963Ah8wZ%2Fj9dkhCeAa7Gs6 > XqJ%2F5SQ%3Dreserved=0 PULL REQUEST: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgith > ub.com%2Fapache%2Fkafka%2Fpull%2F7528data=02%7C01%7Csenthilm%40mi > crosoft.com%7C686c32fa4a554d61ae1408d756d409f6%7C72f988bf86f141af91ab2 > d7cd011db47%7C1%7C0%7C6370733
RE: [DISCUSS] KIP-280: Enhanced log compaction
Hi Tom, Sorry for the delayed response. Regarding the fall back to offset decision for both timestamp & header value is based on the previous author discuss https://lists.apache.org/thread.html/f44317eb6cd34f91966654c80509d4a457dbbccdd02b86645782be67@%3Cdev.kafka.apache.org%3E and as per the discussion, it is really required to avoid duplicates. And the timestamp strategy is from the original KIP author and we are keeping it as is. Finally on the sequence order guarantee by the producer, it is not feasible on waiting for ack in async / multi-threads/processes scenarios and hence the header sequence based compact strategy with producer's responsibility to have a unique sequence generation for the topic-partition-key level. Hoping this clarifies all your questions. Please let us know if you have any further questions. @Guozhang Wang / @Matthias J. Sax, I see you both had a detail discussion on the original KIP with previous author and it would great to hear your inputs as well. Thanks, Senthil -Original Message- From: Tom Bentley Sent: Tuesday, October 22, 2019 2:32 AM To: dev@kafka.apache.org Subject: Re: [DISCUSS] KIP-280: Enhanced log compaction Hi Senthilnathan, In the motivation isn't it a little misleading to say "On the producer side, we clearly preserve an order for the two messages, "? IMHO, the semantics of the producer are clear that having an V2>observed order of sending records from different producers is not sufficient to guarantee ordering on the broker. You really need to send the 2nd record only after the 1st record is acked. It's the difficultly of achieving that in practice that's the true motivation for your KIP. I can see the attraction of using timestamps, but it would be helpful to explain how that really solves the problem. When the producers are in different processes on different machines you're relying on their clocks being synchronized, which is a whole subject in itself. Even if they're synchronized the resolution of System.currentTimeMillis() is typically many milliseconds. If your producers are in different threads of the same process that could be a real problem because it makes ties quite likely. And you don't explain why it's OK to resolve ties using the offset. The basis of your argument is that the offset is giving you the wrong answer. So it seems to me that using it as a tiebreaker is just narrowing the chances of getting the wrong answer. Maybe none of this matters for your use case, but I think it should be spelled out in the KIP, because it surely would matter for similar use cases. Using a sequence at least removes the problem of ties, but the interesting bit is now in how you deal with races between threads/processes in getting a sequence number allocated (which is out of scope of the KIP, I guess). How is resolving that race any simpler that resolving the motivating race by waiting for the ack of the first record sent? Kind regards, Tom On Mon, Oct 21, 2019 at 9:06 PM Senthilnathan Muthusamy wrote: > Hi All, > > We are bring back the KIP-280 to live with small correct for the > discussion & voting. Thanks to previous author Luis Cabral on the > KIP-280 initiation and we are taking over to complete and get it into 2.4... > > Below is the correction that we made to the existing KIP-280: > > * Allowing the compact strategy configuration at the topic level as > the log compaction is at the topic level and a broker can have > multiple topics. This allows the flexibility to have the strategy at > both broker level (i.e. for all topics within the broker) and topic > level (i.e. for a subset of topics within a broker) as well... > > KIP-280: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcwik > i.apache.org%2Fconfluence%2Fdisplay%2FKAFKA%2FKIP-280%253A%2BEnhanced% > 2Blog%2Bcompactiondata=02%7C01%7Csenthilm%40microsoft.com%7C686c3 > 2fa4a554d61ae1408d756d409f6%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0 > %7C637073341017520406sdata=KrRem2KWCBscHX963Ah8wZ%2Fj9dkhCeAa7Gs6 > XqJ%2F5SQ%3Dreserved=0 PULL REQUEST: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgith > ub.com%2Fapache%2Fkafka%2Fpull%2F7528data=02%7C01%7Csenthilm%40mi > crosoft.com%7C686c32fa4a554d61ae1408d756d409f6%7C72f988bf86f141af91ab2 > d7cd011db47%7C1%7C0%7C637073341017520406sdata=bt32PgDUjJjpXohEWpt > Fxv6mPERCwcRFlVROzinBtnk%3Dreserved=0 (unit test coverage in > progress) > > Previous Thread DISCUSS: > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Flist > s.apache.org%2Fthread.html%2F79aa6e50d7c737ddf83455dd8063692a535a1afa5 > 58620fe1a1496d3%40%253Cdev.kafka.apache.org%253Edata=02%7C01%7Cse > nthilm%40microsoft.com%7C686c32fa4a554d61ae1408d756d409f6%7C72f988bf86 > f141af91ab2d7cd011db47%7C1%7C0%7C637073341017520406sdata=XwcUWWYD > PV1nA%2BbkDGLFNlXZ5by
[DISCUSS] KIP-280: Enhanced log compaction
Hi All, We are bring back the KIP-280 to live with small correct for the discussion & voting. Thanks to previous author Luis Cabral on the KIP-280 initiation and we are taking over to complete and get it into 2.4... Below is the correction that we made to the existing KIP-280: * Allowing the compact strategy configuration at the topic level as the log compaction is at the topic level and a broker can have multiple topics. This allows the flexibility to have the strategy at both broker level (i.e. for all topics within the broker) and topic level (i.e. for a subset of topics within a broker) as well... KIP-280: https://cwiki.apache.org/confluence/display/KAFKA/KIP-280%3A+Enhanced+log+compaction PULL REQUEST: https://github.com/apache/kafka/pull/7528 (unit test coverage in progress) Previous Thread DISCUSS: https://lists.apache.org/thread.html/79aa6e50d7c737ddf83455dd8063692a535a1afa558620fe1a1496d3@%3Cdev.kafka.apache.org%3E Previous Thread VOTE: https://lists.apache.org/thread.html/b2ecd73ce849741f0c40b4f801c3f7650583497812713e240e1ac2b7@%3Cdev.kafka.apache.org%3E Appreciate your timely action. PS: Initiating a separate thread as I was not able to reply to the existing threads... Thanks, Senthil
