> `removeMostServicingBrokersForNamespace ` is introduced by [1] to solve the problem that when all bundles in a particular namespace belong to 1 or few machines, customers owning that namespace will be heavily impacted if that broker goes down. Of course, this PR caused the infinite unloading issue and we need to fix it.
Thanks for the context. It looks like we can also try to fix the infinite unloading issue. Now, the broker is unloading the bundles without checking the distribution of the bundles under a namespace, but it will check when finding a new owner. Is it possible to check the bundle distribution before unloading the bundles to avoid infinite unloading? Regards, Penghui On Sun, Jul 2, 2023 at 3:28 PM Enrico Olivelli <eolive...@gmail.com> wrote: > +1 > > Enrico > > Il Dom 2 Lug 2023, 06:19 Hang Chen <chenh...@apache.org> ha scritto: > > > +1 for cherry-picking it to branch-2.10. We have a flag to control > > whether to enable or disable it. > > > > `removeMostServicingBrokersForNamespace ` is introduced by [1] to > > solve the problem that when all bundles in a particular namespace > > belong to 1 or few machines, customers owning that namespace will be > > heavily impacted if that broker goes down. Of course, this PR caused > > the infinite unloading issue and we need to fix it. > > > > > I agree with making it false for the next major version release by > > default. > > We'd better remove the config in the next version instead of change > > the default value to `false`, which will make Pulsar's configuration > > keep increasing. > > > > Thanks, > > Hang > > > > [1] https://github.com/apache/pulsar/pull/388 > > > > PengHui Li <peng...@apache.org> 于2023年7月1日周六 09:38写道： > > > > > > +1 for cherry-pick to branch-2.10 since users don't have a workaround > > > for this issue, and the change is well-understand, low risk. > > > > > > I agree with making it false for the next major version release by > > default. > > > > > > Thanks, > > > Penghui > > > > > > On Sat, Jul 1, 2023 at 9:26 AM Heesung Sohn > > > <heesung.s...@streamnative.io.invalid> wrote: > > > > > > > Hi dev, > > > > > > > > I realized that `removeMostServicingBrokersForNamespace` func in the > > broker > > > > selection logic can cause infinite unloading. > > > > > > > > Suppose an overloaded broker unloaded a bundle and only has the > minimum > > > > number of bundles(in that namespace) among brokers. In that case, the > > > > selection logic (`removeMostServicingBrokersForNamespace`) will > filter > > out > > > > other brokers and always reassign the bundle to the previous broker. > > This > > > > will cause infinite unloading(like a boomerang). > > > > > > > > To mitigate this issue, we need to cherry-pick this PR to disable > this > > > > logic by the config. > > > > https://github.com/apache/pulsar/pull/16059 > > > > > > > > And we probably want to disable this > > > > `removeMostServicingBrokersForNamespace` logic by default. > > > > > > > > Regards, > > > > Heesung > > > > > > >
