This is correct when you send to a topic for the first time. After that the metadata will be cached, the metadata cache has an age and after it expires, metadata will be refreshed. So the time a producer found a broker is not reachable is the minimum value of the following times: 1. Linger.ms + retries * retry.backoff.ms 2. Metadata.max.age.ms 3. Metadata.fetch.timeout.ms (only when sending to a topic for the first time)
Typically you will hit the first one. The default value is linger.ms=0, retries=0. But you need to send records with callback to detect the failure. Jiangjie (Becket) Qin On 3/20/15, 3:46 AM, "Samuel Chase" <samebch...@gmail.com> wrote: >@Sunil > >The else branch will be executed if >`metadata.fetch().partitionsForTopic(topic)` returns non NULL value. I >assume that when Kafka is unreachable, it will return NULL. >`waitOnMetadata()` then returns; we never enter the else branch when >Kafka is unreachable. > >@Everyone: Is this explanation correct? > >On Fri, Mar 20, 2015 at 3:56 PM, sunil kalva <sambarc...@gmail.com> wrote: >> @Samuel >> My point was >> The else branch of the code will be executed when metadata is not >> available, and metadata is not available when kafka cluster is not >>rachable. >> >> please correct me if i am wrong.. >> >> On Fri, Mar 20, 2015 at 3:43 PM, Samuel Chase <samebch...@gmail.com> >>wrote: >> >>> @Sunil >>> >>> On Fri, Mar 20, 2015 at 3:36 PM, sunil kalva <sambarc...@gmail.com> >>>wrote: >>> > I think KafkaProducer.send method blocks until it fetches partition >>> > metadata for configured time using "metadata.fetch.timeout.ms", once >>> time >>> > out it throws TimeoutException. You might be experiencing >>> TimeoutException ? >>> >>> My co-worker pointed out that over here: >>> >>> >>>https://github.com/apache/kafka/blob/0.8.2/clients/src/main/java/org/apa >>>che/kafka/clients/producer/KafkaProducer.java#L368 >>> >>> waitOnMetadata just returns. The else branch of the code is not >>> executed when Kafka is unreachable. >>> >>> Trying to investigate what else must be causing the wait. >>> >> >> >> >> -- >> SunilKalva
