The reduction on network cost is a valid point: letting the consumer to do the filtering would waste the network bandwidth as many bytes would be dropped on the floor directly afterwards. But note that letting brokers to filter on fetch response means that we cannot use nio zero-copy as we need to do this filtering by allocating the memory in user space which could be a big burden at broker-side.
Xianyuan: have you considered using different topics instead, i.e. having a finer-grained grouping of messages based on the consumer subscriptions? Guozhang On Wed, Aug 28, 2019 at 8:14 AM Adam Bellemare <adam.bellem...@gmail.com> wrote: > I do not think this will be implemented in the server. Why not simply > create a consumer that filters as required and outputs to a new topic? > > > On Aug 28, 2019, at 7:48 AM, Xiangyuan LI <flashmouse2...@gmail.com> > wrote: > > > > Hi, > > I want to know whether kafka has any plan to filter message on > > server-side.this can reduce network flow obviously when many groups > > subscribe the same one topic and only need part of message. > -- -- Guozhang
