Yes, that's related to the zombie consumer. Basically, if a consumer is in a long GC, it may be taken out of the group. However, when the consumer wakes up from the GC, it may still be able to consume data that it's no longer responsible for. We protect this a little bit by not allowing a zombie consumer to commit offsets. However, there could be duplicated read. So, it's related to the single-writer in that if we can fence off the zombie consumer, we can eliminate or reduce duplicate reads.
Thanks, Jun On Tue, Aug 18, 2015 at 1:42 PM, Flavio Junqueira <f...@apache.org> wrote: > Thanks for the notes, Jun. There was a mention of single-writer behavior, > if I understood correctly, in the context of the new consumer, and I was > wondering if that's specific to the new consumer work or if it's going to > have any dependency or relation to KIP-27. > > -Flavio > > > On 18 Aug 2015, at 20:20, Jun Rao <j...@confluent.io> wrote: > > > > The the following are the notes for today's KIP discussion. > > > > * client-side assignment strategy: We discussed concerns about > rebalancing > > time due to metadata inconsistency, especially when lots of topics are > > subscribed. Will discuss a bit more on the mailing list. > > > > * CopyCat data api: The discussions are in KAFKA-2367 for people who are > > interested. > > > > * 0.8.2.2: We want to make this a low risk bug fix release since 0.8.3 > is > > coming. So, will only include a small number of critical and small fixes. > > > > * 0.8.3: The main features will be security and the new consumer. We will > > be cutting a release branch when the major pieces for these new features > > have been committed. > > > > The link to the recording will be added to > > > https://cwiki.apache.org/confluence/display/KAFKA/Kafka+Improvement+Proposals > > in a day or two. > > > > Thanks, > > > > Jun > > > > > > > > > > > > On Mon, Aug 17, 2015 at 2:54 PM, Jun Rao <j...@confluent.io> wrote: > > > >> Hi, Everyone, > >> > >> We will have a Kafka KIP meeting tomorrow at 11am PST. If you plan to > >> attend but haven't received an invite, please let me know. The > following is > >> the agenda. > >> > >> Agenda > >> 1. Discuss the proposal on client-side assignment strategy ( > >> > https://cwiki.apache.org/confluence/display/KAFKA/Kafka+Client-side+Assignment+Proposal > >> ) > >> 2. Discuss comments on CopyCat data api (KAFKA-2367) > >> 3. Kafka 0.8.2.2 release > >> 4. Review Backlog > >> > >> > https://issues.apache.org/jira/issues/?jql=project%20%3D%20KAFKA%20AND%20status%20%3D%20%22Patch%20Available%22%20ORDER%20BY%20updated%20DESC > >> > >> > >> Thanks, > >> > >> Jun > >> > >
