Hi, The following is my perspective.
(1) The function name should be resource-control on the storage group level, rather than multi-tenancy. (2) This PR does not bring many side effects as it is disabled by default, so a revert is not a must. (3) The code may need to be improved, but it's ok as long as we keep optimizing. Thanks, ————————————————— Jialin Qiao Apache IoTDB PMC Chao Wang <[email protected]> 于2023年4月10日周一 19:14写道： > > Agree with Houliang's opinion. > > > Thanks! > > > Chao Wang > BONC ltd > On 4/10/2023 19:01，Houliang Qi<[email protected]> wrote： > -1 > > First of all, thanks Xiangdong for pointing out IoTDB's Charter. > > "RESOLVED, that the Apache IoTDB Project be and hereby is > responsible for the creation and maintenance of software > related to an IoT native database with high performance > for data management and analysis, on the edge and the cloud." > > As the charter post, IoTDB can be deployed in the cloud, this is why we > deploy the multi-tenancy feature. > > The cloud can be a public or private cloud if we can deploy only one IoTDB > cluster, and manage multi databases and users with different resources, which > will simplify the maintenance. > > -> 1) how many side-effects the feature will bring; > > We have done some tests under[1], which says with 20 databases and 1 user > when we set `quota_enable` to true to enable the multi-tenancy feature, the > write performance is only slowed down 1.75%, the read latency has not much > difference, we will do more tests to show the side-effects in the feature. > > -> 2) how to reduce the effect when IoTDB is deployed on the edge. > > We supply one switch about this feature, called `quota_enable`, by default > this value is false, so it has no effect when IoTDB is deployed on the edge. > This also answers Jinrui's doubt. > > -> 3) some checks failed on WinOS, are they irrelevant? > > No, I think they are not irrelevant, the false check message is about the > Compaction module, and > I see the former pr[2][3] which have been merged 4 days ago has the same > issue, so I suspect that the compaction module has occasional bugs > > -> 4) The feature SHOULD be discussed carefully in the community, rather that > submit PRs and merged after some reviews. > > Besides the above, when we merge this pr, we posted the design in the > feishu[4] and discussed it online as least two times, and emailed and > discussed it with everyone[5], it has been passed 10 days. > > > The IoTDB community is open and different opinions are welcome. After all, we > all have the same original intention of wanting IoTDB's features to be more > diverse. > > [1] https://apache-iotdb.feishu.cn/docx/DbqCd8t3EoxlCFx1yYicd9N4n4s > [2] https://github.com/apache/iotdb/actions/runs/4625220921/jobs/8181102446 > [3] https://github.com/apache/iotdb/actions/runs/4531046594/jobs/7980725316 > [4] https://apache-iotdb.feishu.cn/docx/doxcnKOYKDmJ40FpVnVsPMd3nTg > [5] https://lists.apache.org/thread/y6dqcm2o7qk0nbkllb61bp8cv6d3m1h7 > > > > > > Thanks, > --------------------------------------- > Houliang Qi > BONC, Ltd > > > ---- Replied Message ---- > | From | 张金瑞<[email protected]> | > | Date | 04/10/2023 15:03 | > | To | dev<[email protected]> | > | Subject | Re：[discuss] consider revert the feature of multi-tenancy | > +1, > > > Agree with Xiangdong's opinion. > And on the other hand, checking this PR's side effects may take lot of > time and during this period, there may be lots of users using latest > code to deploy/upgrade their systems. So the best practice is reverting this > PR until the side-effect is eliminated > > > > Thanks, > Zhang Jinrui，Apache IoTDB PMC > > > > Original > > > > From:"Xiangdong Huang"< [email protected] >; > > Date:2023/4/10 10:05 > > To:"dev"< [email protected] >; > > Subject:[discuss] consider revert the feature of multi-tenancy > > > Hi all, > > I see the multi-tenancy feature is merged, and several committers made > a lot of contributions on that. > > As multi-tenancy is quite a big feature, which may change IoTDB's > position. The feature SHOULD be discussed carefully in the community, > rather that submit PRs and merged after some reviews. > > Therefore, I call to revert the PR and discuss ASAP about the feature > after that. > > At least, the proposer need to answer the following questions, > 1) how many side-effect the feature will bring; > 2) how to reduce the effect when IoTDB is deployed on the edge. > 3) some checks failed on WinOS, are they irrelevant? > > I don't mean of rejecting any big contribution to IoTDB or harming the > community's diversity, but accepting this feature is really big > decision and it deserves us to take time to deliberate. > > > Attached IoTDB's Charter: > "RESOLVED, that the Apache IoTDB Project be and hereby is > responsible for the creation and maintenance of software > related to an IoT native database with high performance > for data management and analysis, on the edge and the cloud." > > > [1] https://github.com/apache/iotdb/pull/9534/checks > > Best, > ----------------------------------- > Xiangdong Huang > School of Software, Tsinghua University
