Hi Abhijeet, Thanks for the KIP! Looks good to me. I just have a minor comments on naming:
Would it be work to align the config names to existing quota names? e.g. `remote.log.manager.copy.byte.rate.quota` (or similar) instead of `remote.log.manager.copy.max.bytes.per.second`? Same for new components, could we use the same verbs as in the configs: - RLMCopyQuotaManager - RLMFetchQuotaManager On Fri, 8 Mar 2024 at 13:43, Abhijeet Kumar <abhijeet.cse....@gmail.com> wrote: > Thank you all for your comments. As all the comments in the thread are > addressed, I am starting a Vote thread for the KIP. Please have a look. > > Regards. > > On Thu, Mar 7, 2024 at 12:34 PM Luke Chen <show...@gmail.com> wrote: > > > Hi Abhijeet, > > > > Thanks for the update and the explanation. > > I had another look, and it LGTM now! > > > > Thanks. > > Luke > > > > On Tue, Mar 5, 2024 at 2:50 AM Jun Rao <j...@confluent.io.invalid> wrote: > > > > > Hi, Abhijeet, > > > > > > Thanks for the reply. Sounds good to me. > > > > > > Jun > > > > > > > > > On Sat, Mar 2, 2024 at 7:40 PM Abhijeet Kumar < > > abhijeet.cse....@gmail.com> > > > wrote: > > > > > > > Hi Jun, > > > > > > > > Thanks for pointing it out. It makes sense to me. We can have the > > > following > > > > metrics instead. What do you think? > > > > > > > > - remote-(fetch|copy)-throttle-time-avg (The average time in ms > > remote > > > > fetches/copies was throttled by a broker) > > > > - remote-(fetch|copy)-throttle-time--max (The maximum time in ms > > > remote > > > > fetches/copies was throttled by a broker) > > > > > > > > These are similar to fetch-throttle-time-avg and > > fetch-throttle-time-max > > > > metrics we have for Kafak Consumers? > > > > The Avg and Max are computed over the (sliding) window as defined by > > the > > > > configuration metrics.sample.window.ms on the server. > > > > > > > > (Also, I will update the config and metric names to be consistent) > > > > > > > > Regards. > > > > > > > > On Thu, Feb 29, 2024 at 2:51 AM Jun Rao <j...@confluent.io.invalid> > > > wrote: > > > > > > > > > Hi, Abhijeet, > > > > > > > > > > Thanks for the reply. > > > > > > > > > > The issue with recording the throttle time as a gauge is that it's > > > > > transient. If the metric is not read immediately, the recorded > value > > > > could > > > > > be reset to 0. The admin won't realize that throttling has > happened. > > > > > > > > > > For client quotas, the throttle time is tracked as the average > > > > > throttle-time per user/client-id. This makes the metric less > > transient. > > > > > > > > > > Also, the configs use read/write whereas the metrics use > fetch/copy. > > > > Could > > > > > we make them consistent? > > > > > > > > > > Jun > > > > > > > > > > On Wed, Feb 28, 2024 at 6:49 AM Abhijeet Kumar < > > > > abhijeet.cse....@gmail.com > > > > > > > > > > > wrote: > > > > > > > > > > > Hi Jun, > > > > > > > > > > > > Clarified the meaning of the two metrics. Also updated the KIP. > > > > > > > > > > > > kafka.log.remote:type=RemoteLogManager, > > name=RemoteFetchThrottleTime > > > -> > > > > > The > > > > > > duration of time required at a given moment to bring the observed > > > fetch > > > > > > rate within the allowed limit, by preventing further reads. > > > > > > kafka.log.remote:type=RemoteLogManager, > name=RemoteCopyThrottleTime > > > -> > > > > > The > > > > > > duration of time required at a given moment to bring the observed > > > > remote > > > > > > copy rate within the allowed limit, by preventing further copies. > > > > > > > > > > > > Regards. > > > > > > > > > > > > On Wed, Feb 28, 2024 at 12:28 AM Jun Rao > <j...@confluent.io.invalid > > > > > > > > wrote: > > > > > > > > > > > > > Hi, Abhijeet, > > > > > > > > > > > > > > Thanks for the explanation. Makes sense to me now. > > > > > > > > > > > > > > Just a minor comment. Could you document the exact meaning of > the > > > > > > following > > > > > > > two metrics? For example, is the time accumulated? If so, is it > > > from > > > > > the > > > > > > > start of the broker or over some window? > > > > > > > > > > > > > > kafka.log.remote:type=RemoteLogManager, > > > name=RemoteFetchThrottleTime > > > > > > > kafka.log.remote:type=RemoteLogManager, > > name=RemoteCopyThrottleTime > > > > > > > > > > > > > > Jun > > > > > > > > > > > > > > On Tue, Feb 27, 2024 at 1:39 AM Abhijeet Kumar < > > > > > > abhijeet.cse....@gmail.com > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > Hi Jun, > > > > > > > > > > > > > > > > The existing quota system for consumers is designed to > throttle > > > the > > > > > > > > consumer if it exceeds the allowed fetch rate. > > > > > > > > The additional quota we want to add works on the broker > level. > > If > > > > the > > > > > > > > broker-level remote read quota is being > > > > > > > > exceeded, we prevent additional reads from the remote storage > > but > > > > do > > > > > > not > > > > > > > > prevent local reads for the consumer. > > > > > > > > If the consumer has specified other partitions to read, which > > can > > > > be > > > > > > > served > > > > > > > > from local, it can continue to read those > > > > > > > > partitions. To elaborate more, we make a check for quota > > exceeded > > > > if > > > > > we > > > > > > > > know a segment needs to be read from > > > > > > > > remote. If the quota is exceeded, we simply skip the > partition > > > and > > > > > move > > > > > > > to > > > > > > > > other segments in the fetch request. > > > > > > > > This way consumers can continue to read the local data as > long > > as > > > > > they > > > > > > > have > > > > > > > > not exceeded the client-level quota. > > > > > > > > > > > > > > > > Also, when we choose the appropriate consumer-level quota, we > > > would > > > > > > > > typically look at what kind of local fetch > > > > > > > > throughput is supported. If we were to reuse the same > consumer > > > > quota, > > > > > > we > > > > > > > > should also consider the throughput > > > > > > > > the remote storage supports. The throughput supported by > remote > > > may > > > > > be > > > > > > > > less/more than the throughput supported > > > > > > > > by local (when using a cloud provider, it depends on the plan > > > opted > > > > > by > > > > > > > the > > > > > > > > user). The consumer quota has to be carefully > > > > > > > > set considering both local and remote throughput. Instead, if > > we > > > > > have a > > > > > > > > separate quota, it makes things much simpler > > > > > > > > for the user, since they already know what throughput their > > > remote > > > > > > > storage > > > > > > > > supports. > > > > > > > > > > > > > > > > (Also, thanks for pointing out. I will update the KIP based > on > > > the > > > > > > > > discussion) > > > > > > > > > > > > > > > > Regards, > > > > > > > > Abhijeet. > > > > > > > > > > > > > > > > On Tue, Feb 27, 2024 at 2:49 AM Jun Rao > > <j...@confluent.io.invalid > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > Hi, Abhijeet, > > > > > > > > > > > > > > > > > > Sorry for the late reply. It seems that you haven't updated > > the > > > > KIP > > > > > > > based > > > > > > > > > on the discussion? One more comment. > > > > > > > > > > > > > > > > > > 11. Currently, we already have a quota system for both the > > > > > producers > > > > > > > and > > > > > > > > > consumers. I can understand why we need an additional > > > > > > > > > remote.log.manager.write.quota.default quota. For example, > > when > > > > > tier > > > > > > > > > storage is enabled for the first time, there could be a lot > > of > > > > > > segments > > > > > > > > > that need to be written to the remote storage, even though > > > there > > > > is > > > > > > no > > > > > > > > > increase in the produced data. However, I am not sure about > > an > > > > > > > > > additional remote.log.manager.read.quota.default. The KIP > > says > > > > that > > > > > > the > > > > > > > > > reason is "This may happen when the majority of the > consumers > > > > start > > > > > > > > reading > > > > > > > > > from the earliest offset of their respective Kafka > topics.". > > > > > However, > > > > > > > > this > > > > > > > > > can happen with or without tier storage and the current > quota > > > > > system > > > > > > > for > > > > > > > > > consumers is designed for solving this exact problem. Could > > you > > > > > > explain > > > > > > > > the > > > > > > > > > usage of this additional quota? > > > > > > > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > > > > Jun > > > > > > > > > > > > > > > > > > On Mon, Feb 12, 2024 at 11:08 AM Abhijeet Kumar < > > > > > > > > > abhijeet.cse....@gmail.com> > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > Comments inline > > > > > > > > > > > > > > > > > > > > On Wed, Dec 6, 2023 at 1:12 AM Jun Rao > > > > <j...@confluent.io.invalid > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > Hi, Abhijeet, > > > > > > > > > > > > > > > > > > > > > > Thanks for the KIP. A few comments. > > > > > > > > > > > > > > > > > > > > > > 10. remote.log.manager.write.quota.default: > > > > > > > > > > > 10.1 For other configs, we > > > > > > > > > > > use replica.alter.log.dirs.io.max.bytes.per.second. To > be > > > > > > > consistent, > > > > > > > > > > > perhaps this can be sth like > > > > > > > > > > remote.log.manager.write.max.bytes.per.second. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > This makes sense, we can rename the following configs to > be > > > > > > > consistent. > > > > > > > > > > > > > > > > > > > > Remote.log.manager.write.quota.default -> > > > > > > > > > > remote.log.manager.write.max.bytes.per.second > > > > > > > > > > > > > > > > > > > > Remote.log.manager.read.quota.default -> > > > > > > > > > > remote.log.manager.read.max.bytes.per.second. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > 10.2 Could we list the new metrics associated with the > > new > > > > > quota. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > We will add the following metrics as mentioned in the > other > > > > > > response. > > > > > > > > > > *RemoteFetchThrottleTime* - The amount of time needed to > > > bring > > > > > the > > > > > > > > > observed > > > > > > > > > > remote fetch rate within the read quota > > > > > > > > > > *RemoteCopyThrottleTime *- The amount of time needed to > > bring > > > > the > > > > > > > > > observed > > > > > > > > > > remote copy rate with the copy quota. > > > > > > > > > > > > > > > > > > > > 10.3 Is this dynamically configurable? If so, could we > > > document > > > > > the > > > > > > > > > impact > > > > > > > > > > > to tools like kafka-configs.sh and AdminClient? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Yes, the quotas are dynamically configurable. We will add > > > them > > > > as > > > > > > > > Dynamic > > > > > > > > > > Broker Configs. Users will be able to change > > > > > > > > > > the following configs using either kafka-configs.sh or > > > > > AdminClient > > > > > > by > > > > > > > > > > specifying the config name and new value. For eg. > > > > > > > > > > > > > > > > > > > > Using kafka-configs.sh > > > > > > > > > > > > > > > > > > > > bin/kafka-configs.sh --bootstrap-server > <bootstrap-server> > > > > > > > > --entity-type > > > > > > > > > > brokers --entity-default --alter --add-config > > > > > > > > > > remote.log.manager.write.max.bytes.per.second=52428800 > > > > > > > > > > > > > > > > > > > > Using AdminClient > > > > > > > > > > > > > > > > > > > > ConfigEntry configEntry = new > > > > > > > > > > > > ConfigEntry("remote.log.manager.write.max.bytes.per.second", > > > > > > > > "5242800"); > > > > > > > > > > AlterConfigOp alterConfigOp = new > > AlterConfigOp(configEntry, > > > > > > > > > > AlterConfigOp.OpType.SET); > > > > > > > > > > List<AlterConfigOp> alterConfigOps = > > > > > > > > > > Collections.singletonList(alterConfigOp); > > > > > > > > > > > > > > > > > > > > ConfigResource resource = new > > > > > > > > ConfigResource(ConfigResource.Type.BROKER, > > > > > > > > > > ""); > > > > > > > > > > Map<ConfigResource, Collection<AlterConfigOp>> > > updateConfig = > > > > > > > > > > ImmutableMap.of(resource, alterConfigOps); > > > > > > > > > > adminClient.incrementalAlterConfigs(updateConfig); > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Jun > > > > > > > > > > > > > > > > > > > > > > On Tue, Nov 28, 2023 at 2:19 AM Luke Chen < > > > show...@gmail.com > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > Hi Abhijeet, > > > > > > > > > > > > > > > > > > > > > > > > Thanks for the KIP! > > > > > > > > > > > > This is an important feature for tiered storage. > > > > > > > > > > > > > > > > > > > > > > > > Some comments: > > > > > > > > > > > > 1. Will we introduce new metrics for this tiered > > storage > > > > > > quotas? > > > > > > > > > > > > This is important because the admin can know the > > > throttling > > > > > > > status > > > > > > > > by > > > > > > > > > > > > checking the metrics while the remote write/read are > > > slow, > > > > > like > > > > > > > the > > > > > > > > > > rate > > > > > > > > > > > of > > > > > > > > > > > > uploading/reading byte rate, the throttled time for > > > > > > > upload/read... > > > > > > > > > etc. > > > > > > > > > > > > > > > > > > > > > > > > 2. Could you give some examples for the throttling > > > > algorithm > > > > > in > > > > > > > the > > > > > > > > > KIP > > > > > > > > > > > to > > > > > > > > > > > > explain it? That will make it much clearer. > > > > > > > > > > > > > > > > > > > > > > > > 3. To solve this problem, we can break down the > RLMTask > > > > into > > > > > > two > > > > > > > > > > smaller > > > > > > > > > > > > tasks - one for segment upload and the other for > > handling > > > > > > expired > > > > > > > > > > > segments. > > > > > > > > > > > > How do we handle the situation when a segment is > still > > > > > waiting > > > > > > > for > > > > > > > > > > > > offloading while this segment is expired and eligible > > to > > > be > > > > > > > > deleted? > > > > > > > > > > > > Maybe it'll be easier to not block the RLMTask when > > quota > > > > > > > exceeded, > > > > > > > > > and > > > > > > > > > > > > just check it each time the RLMTask runs? > > > > > > > > > > > > > > > > > > > > > > > > Thank you. > > > > > > > > > > > > Luke > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Nov 22, 2023 at 6:27 PM Abhijeet Kumar < > > > > > > > > > > > abhijeet.cse....@gmail.com > > > > > > > > > > > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > Hi All, > > > > > > > > > > > > > > > > > > > > > > > > > > I have created KIP-956 for defining read and write > > > quota > > > > > for > > > > > > > > tiered > > > > > > > > > > > > > storage. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-956+Tiered+Storage+Quotas > > > > > > > > > > > > > > > > > > > > > > > > > > Feedback and suggestions are welcome. > > > > > > > > > > > > > > > > > > > > > > > > > > Regards, > > > > > > > > > > > > > Abhijeet. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > > > Abhijeet. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > Abhijeet. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > Abhijeet. > > > > > > > > > > > > > > > > > > > > > > > -- > > > > Abhijeet. > > > > > > > > > > > > -- > Abhijeet. >