In 0.7, each producer reconnects to the broker periodically. Messages sent in different socket connections could arrive out of order. Take a look at reconnect.interval in http://kafka.apache.org/07/configuration.html. If you don't use VIP for the producers, you can actually set reconnect.interval to a really large value. In 0.8, there is no reconnect.interval any more. Messages sent from a single producer are expected to arrive in order at the broker, as long as they sent to the same partition in a topic.
Thanks, Jun On Tue, May 21, 2013 at 5:42 PM, Ross Black <ross.w.bl...@gmail.com> wrote: > Hi, > > I am using Kafka 0.7.1, and using SyncProducer and SimpleConsumer with a > single broker service process. > > I am occasionally seeing messages (from a *single* partition) being > processed out of order to what I expect and I am trying to find where the > problem lies. The problem may well be in my code - I just would like to > eliminate Kafka as a potential cause. > > Messages are being sent sequentially from the producer process, using a > single SyncProducer. > Does Kafka provide any guarantees for message ordering in this case? > > eg. If The sync producer sends messages A then B then C, does the Kafka > broker guarantee that messages will be persisted with the order A,B,C? > If not, is there any way to ensure this ordering? > Has anything changed in 0.8 that could be used to ensure that ordering? > > > Thanks, > Ross >
