Asaf, I don't have numbers to say something about the runtime impact. It is a important feature and I am +1 to enabling it by default
You can send a PR in the meantime. I am not sure about the impact on the tests, maybe we will have to take a look carefully in order to not introduce new flaky tests Enrico Il giorno dom 22 mag 2022 alle ore 18:11 Asaf Mesika <asaf.mes...@gmail.com> ha scritto: > > Resurfacing this as it seems (to me) an important correction to be made. > > Would love your opinions on this. > > Thanks! > > Asaf > > On Wed, May 11, 2022 at 1:16 PM Asaf Mesika <asaf.mes...@gmail.com> wrote: > > > Hello all, > > > > I have a question regarding a feature introduced in 2.6.0 called Negative > > Acknowledgement in Batch Level index, described in PIP-54 > > <https://github.com/apache/pulsar/wiki/PIP-54:-Support-acknowledgment-at-batch-index-level> > > . > > > > In short: Before this feature, if you would write in batches (in producer) > > to Pulsar (which makes sense most would for performance reasons), then a > > consumer sending a negative acknowledgment for 1 message in the batch (say > > we have 500 in a single batch), would cause the consumer to get the all > > messages in the batch (500) redelivered as if they were not acknowledge. > > > > PIP-54 fixes that by keeping the ack per message in a batch using a bitmap > > index. The caveats are more memory consumption since the broker keeps those > > bitmaps in-memory for any inflight batch. > > > > With PIP-54 Pulsar IMO becomes "complete" in that it acts the way you > > would expect it to be, in normal circumstances (as opposed to disconnects, > > machine crashing, etc). > > > > This feature was introduced in 2.6.0, roughly 2 years ago, and is off by > > default. > > > > I was wondering what the developers community thoughts on turning it on by > > default? Has anyone experienced any performance degradation to it? Have you > > turned it on in your clusters? > > > > Thanks a lot for your time. > > > > Asaf Mesika > >
