oops, I think I found my answer in a few mails below: and if i am not mistaken that is why my only consumer is only writing to one partition out of 50.
Hi Michał, Internally, Kafka uses "*consumer group ID*" as the key to decide which __consumer_offsets partition to be used. The code is like this: `Utils.abs(groupId.hashCode) % groupMetadataTopicPartitionCount` You can check the `partitionFor` method in GroupMetadataManager class. Hope that helps. Thank you. Luke On Fri, Sep 10, 2021 at 3:29 PM David Ballano Fernandez < dfernan...@demonware.net> wrote: > Hi all, > > I am running kafka 2.7 in the cluster and only has one consumer reading > from it multiple topics. > I just find out looking at the __consumer_offset topic that only one > partition of that topic is being written to? > > Is that normal? > > thank you! >
